op chem 3 Flashcards
(274 cards)
1
Q
1.Smoke of tobacco is injurious to health because it contains - (A) Carbon Monoxide (B) Nicotine (C) Polycyclic Hydro carbon (D) Methylene
A
(B) [SSC Steno 2010] Exp: Smoke of tobacco contains Nicotine. Effect of Nicotine- (i) Releases adrenaline, increase heart beat rate and blood pressure. (ii) High concentration of nicotine paralyse nerve cells (iii) Retards foetal growth in expecting mothers.
2
Q
2.Producer gas is highly poisonous due to the presence of- (A) Nitrogen (B) Carbon Monoxide (C) Hydrogen sulphide (D) Sulphur dioxide
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(B) [SSC MTS 2014] Exp: Producer gas is a mixture of gases mainly nitrogen and carbon monoxide. Due to presence of carbon monoxide producer gas is highly poisonous.
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3.Which gas causes suffocation and death when coal is burnt in a closed room? (A) Ethane (B) Carbon dioxide (C) Carbon Monoxide (D) Methane
A
(C) Exp: Carbon monoxide is produced due to incomplete combustion of coal. Toxic nature of CO is due to its ability to form a complex carboxy-haemoglobin which is about 300 times more stable than oxyhaemoglobin complex. This prevents haemeoglobin to carry oxygen there by causing suffocation ultimately leading to death.
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4.It is not advisable to sleep under the tree at night because trees release- (A) Carbon dioxide (B) Oxygen (C) Carbon monoxide (D) Sulphur dioxide
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(A) [SSC CPO 2012] Exp: Plants release CO2 at night. At night respiration is predominant over photosynthesis because sun light is absent (sun light is necessary for photosynthesis). So, O2 gas concentration becomes low.
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5.Air pollutant contains - (A) Radiations and gases(B) Only Liquid (C) Only gases (D) Only radiations
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(A) [SSC MTS 2014] Exp: Air pollutant contains gaseous materials particulate matter and radioactive substances which emit radiations. Gaseous pollutants contain oxides of carbon (CO & CO2), oxides of nitrogen (NO & NO2), oxides of sulphur (SO2 & SO3), Hydrocarbons, photochemical oxidants (PAN, Ozone, Smog, Aldehydes) etc.
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6.Oxides of sulphur present in atmosphere washed down by rain to cause- (A) Industrial Smog (B) Depletion of fossil fuel reserves (C) Eutrophication in Lakes (D) Lowering of pH of soil
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(D) [SSC GD 2015] Exp: Oxides of sulphur present in atmosphere react with rain water to form Sulphuric Acid. Acids decreases pH value of soil.
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7.Green House effect means - (A) Farming in green Houses for the conservation of energy. (B) Trapping of solar energy due to carbon dioxide. (C) Trapping of solar energy by the upper layer of earth. (D) Increase in temperature due to atmospheric pollution.
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(B) [SSC MTS 2013] Or Green House Effect means (A) Pollution in houses in tropical region (B) Prevention of ultra-violet radiation by the ozone layer (C) Trapping of solar energy due to atmospheric gases (D) Damage to green painted buildings (C) (SSC CGL 2016) Exp: Green house effect means trapping of solar energy due to atmospheric gases. CO2, CH4, CFC, N2O are green house gases. The warming of earth or global warming due to the trapping of infrared radiations reflected from the earth’s surface by CO2 layer in the atmosphere is called green house effect.
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Which of the following atmospheric gases are green House gases. [SSC MTS 2013] Or Which of the following affect more ‘Green House effect’? (SSC MTs 2011) 1. Carbon dioxide 2. Nitrogen 3. Nitrous Oxide 4. Water vapours (A) 1,3 and 4 (B) 1 and 4 (C) 1 and 3 (D) 1, 2 and 4
A
(A) Exp: The relative contribution of different green house gases to global warming are - Carbon dioxide (CO2) - 60% Methane (CH4)- 20% Chlorofluoro carbons (CFC) - 14%, Nitrous Oxide (N2O) - 6% Water vapour and Ozone contribution is negligible.
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9.Which one of the following pollutant is responsible for the ozone Hole? (A) CO2 (B) SO2 (C) CO (D) CFC
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(D) [SSC CGL 2014] Exp: CFC (Chloro Fluorocarbon) is responsible for the Ozone Hole.
10
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10.Which one of the following metal highly pollute the water? (A) Arsenic (B) Lead (C) Magnesium (D) Potassium
A
(A) [SSC LDC 2005] Exp: Arsenic in compound state is found at most of the places over earth. In the vapours of volcano, ocean and in many mineral water. It is responsible for the high pollution of water.
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Q
11.Phenolics as Pollutant can be removed from waste water by use of- (A) Ion exchange method (B) Reverse osmosis method (C) Electrolytic decomposition technique (D) Polymeric adsorbents
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(A) [SSC CGL 2012] Exp: Phenolics as pollutant is removed from waste water by Ion exchange method. Ion exchange method is also used in separation of metals, catalytic processes, medicines, purification of Juice and in the production of sugar.
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12.Highly polluting industries comes under the category of- (A) Orange (B) Red (C) Yellow (D) Black
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(B) [SSC CHSL 2012] Exp: According to Forest Environment ministry highly polluting industries are categorized in red category.
13
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13.Which of the following Agriculture practices have been primarily responsible for the pollution of our water resources? 1. Use of Live Stock Manure 2. Use of chemical fertilizer 3. Excessive use of chemical pesticides 4. Deforestation(A) 1 and 2 (B) 1, 2 and 4 (C) 2 and 3 (D) 1, 3 and 4
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(C) [SSC CHSL 2012] Exp: Modern agriculture practices include excessive use of chemical fertilizers and pesticides which pollutes water resources.
14
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14.Which one of the following does not causes any pollution? (A) Burning of Rubber (B) Burning of petrol (C) Use of solar energy (D) All of these
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(C) [SSC CHSL 2012] Exp: Solar energy does not cause any pollution, while burning of rubber produces carbon dioxide and sulphur dioxide. Burning of Petrol also produces carbon dioxide, carbon Monoxide, sulphur dioxide etc.
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15.BOD value of water indicates the- (A) Amount of organic debris (B) Amount of oxygen, used for biochemical oxidation (C) Amount of oxygen, used for biochemical reduction. (D) Amount of ozone, used for biochemical oxidation.
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(B) [SSC FCI Exam, 2012] Exp: BOD (Biochemical oxygen demand) indicates the amount of oxygen used for the biochemical oxidation.Greater the value of BOD, higher will be the pollution level.
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16.Which of the following can be found as pollutants in the drinking water in some parts of India. 1. Arsenic 2. Orbital 3. Fluoride 4. Formaldehyde 5. Uranium (A) 2, 4 and 5 (B) 1 and 3 (C) 1, 2, 3, 4 and 5 (D) 1, 3 and 5
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(D) [SSC CGL 2015] Exp: Generally the water we drink contains a lot of chemical impurities. In some parts of India water pollutants are found in drinking water are Arsenic, Fluoride and uranium (in Punjab) etc.
17
Q
17.Size of suspended particles lies between- (A) 10-2 - 10-4 Aº (B) 10-5 - 10-7 Aº (C) 10-8 - 10-10 Aº (D) 10-1 - 10-2 Aº
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(B) [SSC MTS Exam, - 2013] Exp: Size of suspended particle Lies between 10-5 - 10-7 A0
18
Q
18.Main Constituent of air is- (A) Nitrogen (B) Carbon dioxide (C) Oxygen (D) Hydrogen
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(A) [SSC Tax asst. 2007] Exp: The composition of air is as follows. Nitrogen = 78%, Oxygen = 21%, CO2 = 0.032% and small amount of other gases. Ar = 0.93%.
19
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19.Which atmospheric gas absorbs ultraviolet rays? (A) Ozone (B) Methane (C) Nitrogen (D) Helium
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(A) [SSC MTS 2011] Exp: Ozone is an allotrope of oxygen. Ozone molecule contains 3 oxygen atoms (O3). In the stratosphere, Ozone is being photodissociated and generated by the absorption of short wavelength ultraviolet (UV) radiatons. O3 UV radiations O2 + [O] Absorption of UV radiations by ozone blanket is proportional to its thickness. Thickness of ozone is expressed in Dobson units (DU).
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Q
20.Super Sonic Jet causes pollution by thinning of- (A) O3 Layer (B) SO2 Layer (C) O2 Layer (D) CO2 Layer
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(A) [SSC CGL 2011] Exp: Supersonic Jet causes pollution by thinning Layer of O3 (Ozone). Ozone Layer protects earth from ultraviolet radiation coming direct from sun.
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21.Bhopal Gas Tragedy was caused by - [Steno 2011, Tax Asst. 2006, MTS 2002] Or Which pollutant is mainly responsible for the Bhopal Gas tragedy? [SSC CHSL 2013] (A) Nitrogen (B) Carbon monoxide (C) Chlorine (D) Methyl isocyanate
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(D) Exp: Bhopal gas tragedy was caused by methyl isocyanate (MIC) on december 2 1984 in Bhopal (M.P) in the Union Carbide factory. MIC was used to manufacture the insecticide.
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Q
22.Permissible concentration of residual chlorine in drinking water in mg/L is - (A) 1.0 (B) 5.0 (C) 0.2 (D) 0.05
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(C) [SSC CHSL 2012] Exp: According to WHO, permissible concentration of residual chlorine in drinking water is upto 0.5 mg/L. 0.2 mg/L is the nearest value to 0.5 mg/L in the given options.
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Q
23.The most abundant Nob le gas in the atmosphere is - (A) Helium (B) Neon (C) Argon (D) Krypton
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(C) [SSC CPO 2008] Exp: Except Radon, all Noble gases are present in the atmosphere and out of them argon (0.93%) is most abundant.
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24.The largest source of pollution in the world is (A) Herbicides and insecticides (B) Automobile exhausts (C) Sewage and garbage (D) Industrial effluents
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(C) (SSC CGL 2016) Exp: The largest source of pollution in world is sewage and garbage. Sewage is a type of waste water that is produced from a community of people. It consists mostly of grey water (from showers, sinks, dishwashers and clothes washers) blackwater (water used to flush toilets combined with the human waste), soaps and detergents and toilet paper. While garbage is an undesired or unwanted substance discarded by residents.
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25.Acid rain is caused due to pollution of atmosphere by (A) Oxides of nitrogen and sulphur (B) Oxides of nitrogen and phosphorous (C) Oxides of carbon and nitrogen (D) Oxides of nitrogen and methane
(A) (SSC CGL 2016) Exp: Acid rain is caused due to pollution of atmosphere by oxides of nitrogen and sulphur. In air, sulphur dioxide (SO2) reacts with water to form sulphuric acid (H2SO4) and Nitrogen dioxide (NO2) reacts with water to form Nitric acid (HNO3). Acid rain has pH less than 5.6
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26.A level of atmosphere which is composed partly of electrons and positive ions is called (A) Troposphere (B) Ionosphere (C) Stratosphere (D) Mesosphere
(B) (SSC CGL 2016) Exp: Mesosphere and thermosphere (collectively called ionosphere) contain gases (N2, O2, O2 , NO+, etc.) in the ionized form. These ions reflect back the radio waves to the earth.
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27.The most serious air pollutant causing health hazard is (A) Sulphur dioxide (B) Carbon dioxide (C) Ozone (D) Nitrogen oxide
(A) (SSC CGL 2016) Exp: The most serious air pollution causing health hazard is sulphur dioxide. SO2 affects the respiratory system particularly lung function, irritates the skin and mucous membrane of the eyes, nose throat and Lungs.
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28.Why is Carbon monoxide a pollutant because it (A) Reacts with haemoglobin (B) Makes nervous system inactive (C) Reacts with oxygen (D) Inhibits glycolysis
(A) (SSC CGL 2016) Exp: Carbon monoxide is poisonous because it combines with haemoglobin of the RBC about 200 times more easily than does oxygen, to form carboxyhaemoglobin. Hb + CO HbCO Carboxyhaemoglobin.
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29.Which layer of the earth's atmosphere contains the Ozone layer? (A) Troposphere (B) Mesosphere (C) Ionosphere (D) Stratosphere
(D) (SSC CGL 2016) Exp: In the stratosphere, the oxygen started partially being converted into Ozone. At an altitude of 25-30 km, a layer in which the concentration of ozone is about 10 ppm. It is called Ozone layer. Therefore, this region is also called as Ozonosphere.
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30.Sullage water is _______ (A) Waste water released from kitchen (B) Waste water released from toilets (C) Waste water released from factories (D) Waste water released from hospitals
(A) (SSC CGL 2016) Exp: Sullage water is also called gray water. It is a water generated in households sinks, shower and bath without contamination of faecal matter.
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31.Chernobyl disaster is the result of pollution by_______. (A) Oil spill (B) Acid rain (C) Carbon dioxide (D) Radioactive waste
(D) (SSC CGL 2016) Exp: Chernobyl disaster occured on 26 April 1986 in graphite moderated reactor at the Chernobyl nuclear power plant. It was a catastrophic nuclear accident.
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32.Which of the following caused radioactive pollution along the coast of Kerala? (A) Plutonium (B) Zinc (C) Thorium (D) Radium
(C) (SSC CGL 2016) Exp: Monazite sands are ore of thorium. It is found on the sea-coast of Kerala state in India. So, radio-active pollution occurs due to thorium.
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33.Ozone saves the biosphere by absorbing high energy radiations called_______. (A) Infrared rays (IR) (B) Gamma rays (C) Ultraviolet rays (UV) (D) X-rays
(C) (SSC CGL 2016) Exp: Ozone saves the biosphere by absorbing high energy radiations called Ultraviolet rays (UV). Ozone layer acts as shield against UV rays. UV rays damage DNA of skin and cause cancer.
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34.One of the best solutions to get rid of non biodegradable waste is (A) Burning (B) Dumping (C) Burying (D) Recycling
(D) (SSC CGL 2016) Exp: Recycling is the best solution to get rid of non biodegradable waste. Recycling is waste minimization strategy in which reusable materials are recovered from a waste material.
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35.Ultraviolet radiation in the stratosphere is absorbed by (A) SO2 (B) Ozone (C) Oxygen (D) Argon
(B) (SSC CGL 2016) Exp: Ultraviolet radiation in the stratosphere is absorbed by Ozone layer.
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36.The depletion in Ozone layer is caused by_____________. (A) Nitrous oxide (B) Carbon dioxide (C) Chlorofluorocarbons (D) Methane
(C) (SSC CGL 2016) Exp: The depletion of ozone layer is caused by chlorofluoro carbon and Nitric oxide. One chlorine atom can destroy about 1 lakh ozone molecules.
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37.The commonly used coolant in refrigerators is (A) Ammonia (B) Nitrogen (C) Freon (D) Oxygen
(C) (SSC CGL 2016) Exp:Chlorofluorocarbons (CFC) i.e, compounds containing carbon, chlorine and Fluorine commonly known as Freons. These are introduced into the atmosphere from aerosol sprays in which they function as propellants and from refrigerating equipment in which they act as coolant.
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38.What causes the mottling of the dental enamel ? (A) High levels of chlorine in water (B) High levels of nitrate in the water (C) High levels of fluorides in the water (D) High levels of calcium in the water
(C) (SSC CGL 2016) Exp: High level of fluorides (present in drinking water & toothpaste) causes mottling of the Dental Enamel (Dental fluorosis). Black, Brown spots appear in mottled teeth. Permissible limit of Fluoride is 1-1.5 ppm or 1-1.5 mg/dm3.
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39.Which of the following is usually not an airpollutant? (A) Hydrocarbons (B) Sulphur dioxide (C) Carbon dioxide (D) Nitrous oxide
(D) (SSC CGL 2016) Exp: Primary air pollutants are: (i) Oxides of carbon (CO & CO2) (ii) Oxides of Nitrogen (NO & NO2) (iii) Oxides of sulphur (SO2) (iv) Hydrocarbons (CH4) (v) Suspended particulate matter.
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40.Which of the following is the treatment of water pollution? (A) Bag house filter (B) Windrow composting (C) Venturi scrubber (D) Reverse Osmosis
(D) (SSC CGL 2016) Exp: The process of movement of solvent through a semipermeable membrane from the solution to the pure solvent by applying external pressure on solution side is called reverse osmosis. Reverse osmosis is used for the desalination of sea water for getting fresh drinking water.
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41.Besides CO2, the other green house gas is (A) CH4 (B) N2 (C) Ar (D) O2
(A) (SSC CGL 2016) Exp: Greenhouse gases are: Carbon dioxide (CO2)-60%, Methane (CH4)-20% Chlorofluoro carbon (CFC)-14%, Nitrous oxide (N2O)-6%
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42.The most abundant element in the earth's atmosphere is (A) Argon (B) Nitrogen (C) Oxygen (D) Krypton
(B) (SSC CGL 2016) Exp: Earth atmosphere contains Nitrogen-(78.09%) and Oxygen-(20.95%), Argon-(0.934%) and Carbondioxide- (0.034%).
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43.______ is a byproduct of sewage treatment and can be decomposed to produce bio-gas (A) Sewage (B) Sludge (C) Sewer (D) Scum
(B) (SSC CGL 2016) Exp: Sewage treatment involves three stages. Sludge is a semisolid residue produced in first step during treatment of sewage and waste water.
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"44.Who coined the Chipko slogan ""Ecology is Permanent Economy""? (A) Chan Prasad Bhatt (B) Sundarlal Bahuguna (C) Shayam Prasad Bahuguna (D) Bachni Devi"
"(B) (SSC CGL 2016) Exp: Sundarlal Bahuguna coined the Chipko slogan ""Ecology is Permanent Economy"". The first chipko action took place spontaneously in April 1973 in the village of Mandal in the Upper Alaknanda Valley and over the next five years spread to many districts of the Himalayas in Uttarakhand."
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45.Which of the following green house gases has the greatest heat trapping ability? (A) Chlorofluorocarbon (B) Methane (C) Carbon dioxide (D) Nitrous oxide
(A) (SSC CGL 2016) Exp: Chlorofluorocarbon has the greatest heat trapping ability
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46.Particulates (< 1 m size) remaining suspended in air indefinitely and transported by wind currents are called (A) Mists (B) Fumes (C) Aerosols (D) Smoke
(C) (SSC CGL 2016) Exp: Aerosols are colloidal solution of fine solid particles or liquid droplets in air. eg. Haze, dust, fog etc.
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47.The least preferred technique in the disposal of Municipal Solid Waste is (A) Incineration (B) Composting (C) Land filling (D) Briquetting
(D) (SSC CGL 2016) Exp: (i) Incineration:- waste treatment which involves burning. (ii) Compost ing :- Biodegradable garbage is converted into soil rich fertiliser. (iii)Landfill:- Disposal of waste by burial. (iv) Briquetting:- process to convert loose biomass waste like cotton stalks into high density solid blocks which can be further used as fuel
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48.The 'solid waste' is also known as (A) Sedge (B) Toxic waste (C) Sludge (D) Scrubber
(C) (SSC CGL 2016) Exp: Sludge is a solid waste and can be produced from wastewater treatment and during synthesis of Biogas.
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49.Which of the following is a greenhouse gas or a gas which can deplete the ozone layer? (A) BF3 (B) O2 (C) CHClF2 (D) Cl2
(C) (SSC CHSL 2016) Exp: CHClF2 is freon. Freons are the chlorofluorocarbon (CFCs) or hydrochlorofluorocarbons (HCFCs) compounds. They are used as refrigerants and as aerosol propellants. Freons are responsible for Ozone depletion.
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50.Which of the following is a greenhouse gas or a gas which can deplete the ozone layer? (A) BBr3 (B) NH3 (C) CH2N2 (D) CCl2F2
(D) (SSC CHSL 2016) Exp: CCl2F2 is freon. Freons are the chlorofluorocarbon (CFCs) or hydrochlorofluorocarbons (HCFCs) compounds. They are used as refrigerants and as aerosol propellants. Freons are responsible for Ozone depletion.
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51.Which of the following primarily causes lead pollution? (A) CFL Lamp (B) Automobile Industry (C) Polymer (D) Diesel Engine
(B) (SSC CPO 2017) Exp: Automobile industry causes lead pollution. In automobile a compound of lead i.e. tetraethyl lead (C2H5) 4Pb is used as an antiknocking material. Due to this, lead pollution occurs.
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52.What was the main aim of Montreal Protocol? (A) Protection of Ozone layer (B) Bio-diversity Conservation (C) Global Warming (D) Climate Change
(A) (SSC CPO 2017) Exp: The Montreal Protocol is a global agreement to protect the stratospheric Ozone layer.
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53.Supersonic jets cause thinning of which layer? (A) O2 layer (B) O3 layer (C) CO2 layer (D) SO2 layer
(B) (SSC CPO 2017) Exp: Supersonic jets release nitrogen dioxide which has the potential to destroy significant quantity of Ozone in stratosphere. So, thinning of ozone layer occurs.
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54.Which of the following is an air pollutant? I. Water vapour II. Carbon dioxide III. Hydrogen Gas (A) Only I (B) Only II (C) Only III (D) Both II and III
(B) (SSC CPO 2017) Exp: Air pollutants are agents which pollute the air. e.g: Carbon monoxide, Lead, Nitrogen-oxide, Sulphur dioxide & particulate matter are some air pollutants.
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55.Which of the following is a major component of water pollution in Bengal Basin? (A) Chromium (B) Arsenic (C) Calcium (D) Potassium
(B) (SSC CPO 2017) Exp: Arsenic is a major component of water pollution in Bengal Basin due to aeration of arsenopyrites buried in the sediments.
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56.Which of the following is/are CORRECT? (A) SPM - Suspended Particulate Matter (B) COD - Chemical Oxygen Demand (C) None of these (D) Both
(D) (SSC CPO 2017) Exp: SPM - Suspended Particulate Matter COD - Chemical Oxygen Demand
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57.Which of the following primarily produces Nitrogen dioxide leading to air pollution? (A) CFL Lamp (B) Automobile Industry (C) Polymer (D) Diesel Engine
(B) (SSC CPO 2017) Exp: Automobile industry produces the Nitrogen dioxide (NO2) which is responsible for air pollution.
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58.Bleaching liquors are inorganic pollutants produced mainly by which Industry/Industries? I. Paper and Pulp Industry II. Iron and Steel Industry III. Mining Industry (A) Only I (B) Only II (C) Only III (D) Both II and III
(A) (SSC CPO 2017) Exp: Bleaching liquors are inorganic pollutants produced mainly by paper & pulp industry.
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59.Which of the following pair is correct? Pollutants Industry Bleaching liquor Paper & Pulp Cellulose fibres Pharmaceuticals Drugs & Antibiotic Mining (A) only I (B) only II (C) only III (D) Both I and II
(A) (SSC CPO 2017) Exp:Pollutant Industry Bleaching liquor: Paper & Pulp industry Cellulose fibres: Pulp & Paper industry Drug & Antiboitic: Pharmaceutical industry
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60.Cellulose fibres are organic pollutant mainly produced by which Industry/Industries? I. Mining Industry II. Soap and detergent Industry III. Paper and Pulp Industry (A) Only I (B) Only II (C) Only III (D) Both II and III
(C) (SSC CPO 2017) Exp: Cellulose fibres are organic pollutant mainly produced by Paper & Pulp industry. Organic pollutants are those organic compounds which are resistant for degradation by chemical, physical and bio-chemical process. So, they accumulate & pollute wherever they are present.
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61.Match the correct pair/pairs: Pollutant Industry 1. Tertiary ammonium salt - Soap Industry 2. Bleaching liquor - Paper and pulp Industry 3. Cellulose fibres - P h a r m a c e u t i c a l s Industry (A) Only I (B) Only II (C) Only III (D) Both I and II
(D) (SSC CPO 2017) Exp: Product/Pollutant Industry Tertiary Ammonium Salts: Soap Industry Bleaching Liquor: Paper & Pulp industry Cellulose fibres: Paper & pulp industry
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1.Which among the following is an endothermic reaction? (A) Respiration (B) Combustion (C) Sweating (D) Burning of natural gas
(C) (SSC CHSL 2016) Exp: Endothermic reactions involve absorption of heat. Sweating (Also known as perspiration) occurs to maintain body temperature (thermoregulation).
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2.Name the catalyst used in the conversion of milk into curd. (A) Pepsin (B) Invertase (C) Lactase (D) Diastase
(C) (SSC CHSL 2016) Exp: Lactase enzyme works as catalyst in the conversion of milk into curd. Enzymes are known as Biocatalysts.
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3.What does a catalyst do in a reaction? (A) Changes potential energy of reactants (B) Changes kinetic energy of reactants (C) Changes potential energy of products (D) Changes activation energy
(D) (SSC CHSL 2016) Exp: A chemical reaction takes place by a reaction path, first converted to activated state and then finally to the products. Catalyst provides an alternative route for the reaction with a lower activation energy.
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4.The unit of ionic Product of water (Kw) is- (A) Mol2 ltr-1 (B) Mol2 ltr-2 (C) Mol-1 ltr2 (D) Mol-1 ltr-1
(B) [SSC CHSL 2010] Exp: Unit of Concentration is mol/litre. Ionic product of water is represented as- Kw =[H+][OH-] So unit of Ionic product of water will be mole2 litre-2.
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5.Which one of the following has highest value of specific heat? (A) Glass (B) Copper (C) Lead (D) Water
(D) [SSC DEO 2008] Exp: From the given options water has highest value of specific heat. Its value is 1 Cal/g 0C or 4.186 J/g 0C.
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6.Which one of the following is known as solution? (A) Compound (B) Homogeneous mixture (C) Heterogeneous mixture (D) Suspension
(B) [SSC CGL Exam, 2014] Exp: A solution is a homogeneous mixture of two or more substances whose composition can be varied within certain limits.
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7.Electrolysis of copper sulphate solution with copper electrodes gives- (A) Copper at cathode and oxygen at anode (B) Copper at anode and oxygen at cathode (C) Copper dissolve itself to give copper at cathode and anode. (D) Hydrogen at cathode and oxygen at anode
(A) [SSC Steno 2011, SSC CHSL 2010] Exp: Aqueous solution of copper sulphate contains ion of Cu2+, 2- SO4, H+, OH- and Molecules of water. During electrolysis of copper sulphate reduction of Cu2+ into Cu occurs at cathode and OH- ions are oxidized in oxygen at anode.
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8.If the equilibrium constant for the system: H2+I2 2HI and 2HI H2 + I2 are K1 and K2 Respectively, the relationship between K1 and K2 is- (A) K1 = K2 (B) K1 = 2K2 (C) K1 = K2/2 (D) K1 = 1/K2
(D) [SSC CHSL Exam, 2014] Exp: H2+I2 2HI K1 = 2 2 2 HI H I.... (i) 2HI H2 + I2 K2 = 2 2 2 H I HI.... (ii) from equation (ii) and (ii) K1 = 2 1 K or K1.K2 = 1
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9.In a rechargeable cell what kind of energy is stored within the cell?(A) Electric energy (B) Potential energy (C) Kinetic energy (D) Chemical energy
(D) [SSC Sec. off. - 2006] Exp: Chemical energy is stored in a rechargeable cell. A device which stores energy (removed as electrical energy in discharging process) is called as Accumulator or battery.
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10.Which acid is stored in batteries? (A) Hydrochloric acid (B) Sulphuric acid (C) Acetic acid (D) Nitric acid
(B) [SSC CHSL Exam, 2011] Exp: A 38% solution of sulphric acid is used as an electrolyte in lead storage battery. When the density of H2SO4 falls below 1.2 gml-1, the battery needs recharging.
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11.Which of the following pairs of Material is commonly used in rechargeable batteries used in Torch Lights, Electric Shaver etc. (A) Iron and Cadmium (B) Nickel and Cadmium (C) Lead and Lead per oxide (D) Zinc and Carbon
(B) [SSC CGL 2005] Exp: Rearchargeable batteries can be charged again. Ni-Cd, Li ion batteries are secondary batteries.
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12.What happens during the charging of Lead operated battery? (A) SO2 is formed (B) Consumption of Lead Sulphate (C) Lead is Formed (D) Consumption of sulphuric acid
(B) [SSC MTS 2013] Exp: Consumption of lead sulphate (PbSO4) takes place during the charging of lead operated battery. During charging of battery lead is deposited on anode and PbO2 on the cathode & density of sulphuric acid also Increases. 2PbSO4 + 2H2O Charg e Pb + PbO2 + 2H2SO4
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13.Catalyst are those substances- (A) Which increase rate of reaction (B) Which decrease rate of reaction (C) Does not affect the rate of reaction (D) None of these
(A) [SSC CPO Exam, 2006] Exp: Catalyst are the subtance which alter the rate of reaction without being consumed in the reaction. Rate of reaction is defined as the change in any one of the reactant or product per unit time.
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14.When H2 gas is allowed to expand from a region of High pressure to a region of Low pressure the temperature of gas- (A) Decreases to a small extent (B) Increases (C) Does not change (D) Decreases suddenly.
(B) [SSC CGL 2012] Exp: Joule thomson effect-when a real gas is allowed to expand adiabatically from a region of high pressure to a region of low pressure, it is accompanied by cooling (except for hydrogen and helium).
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15.Example of Aerosol is - (A) Milk (B) River water (C) Smoke (D) Blood
(C) [SSC FCI 2012] Exp: Aersols are type of colloid in which solid or liquid is dispersed in gas. eg. smoke, dust, storm, Haze, mist fog, cloud, insecticide spray.
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16.In a reaction of type A + B C + D one could ensure it, to be a First order reaction by- (A) Increasing the concentration of a Product (B) Increasing the concentration of a reactant (C) Increasing the temperature (D) Adding a catalyst
(B) [SSC CHSL 2015] Exp: In a reaction of type A+B C+D one could ensure it to be a first order reaction by increasing the concentration of reactant.
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17.Blood may be purified by- (A) Dialysis (B) electro-osmosis (C) coagulation (D) filteration
(A) Exp: Dialysis: The process of removing the particles from colloidal solution by diffusion process through suitable membranes. Note: Blood is a colloidal solution.
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18.Isotonic solutions have equal. (A) Vapour pressure (B) osmotic pressure (C) boiling point (D) freezing point
(B) Exp: The solutions having same osmotic pressure are called isotonic solutions. Note: 0.91% (m/v) solution of sodium chloride (saline water) is isotonic with fluids inside human Red blood cells (R.B.C). In this solution RBC neither swell nor shrink.
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19.Strong electrolytes are those which - (A) dissolve readily in water (B) conduct electricity. (C) dissociate into ions even at high concentration (D) dissociate into ions at high dilution.
(C) Exp: Strong electrolytes are completely ionised (dissociates) in water. In solution they are excellent conductors. eg- HNO3, HCl, NaOH, KOH etc.
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20.Which of the following is not a crystalline solid?(A) Salt (B) Sugar (C) Copper sulphate (D) Rubber
(D) [SSC LDC 2005] Exp: Rubber is not a crystalline solid but it is an amorphous solid. Examples of Amorphous solid- Rubber, Glass, Plastic, Cement and Paraffin. Examples of crystalline solid- Quartz, Copper Sulphate, rocksalt, Sugar, Mica and diamonds.
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21.The two specific Heats of gases are related by- (A) CP-CV = R (B) CP-CV = R (C) CP/CV = R (D) CP+CV = R
(B) [SSC CGL 2015] Exp: Specific Heat is the amount of Heat required to raise the temperature by 1°C. At a given volume it is used to increase the temperature only. At a given pressure specific Heat at constant pressure is always greater than the specific Heat at constant volume and their relation is expressed as CP - CV = R.
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22.What is the value of Gas constant 'R' in erg per degree per mol? (A) 8.314×107 (B) 8.341×107 (C) 8.413×107 (D) 4.183×107
(A) [SSC MTS 2013] Exp: 8.314×107 erg per degree per mol.
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23. Enzyme which coagulate the milk into curd- (A) Rennin (B) Pepsin (C) Regin (D) Citrate
(A) [SSC Steno 2011] Exp: Rennin enzyme coagulates the milk into curd.
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23.Which one of the following is an Example of gel? (A) Cheese (B) Milk (C) Facial cream (D) None of these
(A) [SSC Steno 2011] Exp: Cheese is an Example of Gel. Gelatin and gelly are Examples of Gel.
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24.What changes will happen to a bowl of ice and water kept at exactly zero degree Celsius? (A) All ice will melt (B) All water will become ice (C) No change will happen (D) Only some ice melts
(C) [SSC CGL 2010] Exp: At 0ºC there will be no change in the bowl of ice and water.
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25.Water and ice crystal are in equilibrium at 0ºC. when pressure is applied to this system- (A) More of the ice becomes water (B) No effective change occur (C) Water changes to vapor (D) More amount of ice is formed
(B) [SSC CPO 2012] Exp: On applying pressure when on the system, there is no effect on the ice and water, when both are in equilibrium at 00C.
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26.Light Scattering take place in- (A) Colloidal solution (B) Acidic Solution (C) Basic Solution (D) Electrolytic Solution.
(A) [SSC CGL 2013] Exp: In a colloidal solution size of particle Lies between 1 nm-1000 nm. These particles causes scattering of Light Scattering of Light can be observed by the Ultra microscope, known as Tyndall effect.
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27.Muddy water is treated w ith alum in Purification process- (A) Coagulation (B) Absorption (C) Emulsification (D) Adsorption
(A) [SSC CGL 2015] Exp: By Coagulation process, Muddy water can be converted into clean water. Alum is added to muddy water, then by coagulation, Flocculation and sedimentation we get clean water.
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28.Alum is used for the water treatment in the process named- (A) Coagulation (B) Peptization (C) Softening (D) Electro osmosis
(A) [SSC FCI 2012] Exp: Alum is used in the process coagulation. Its chemical name is Potassium aluminate sulphate [K2SO4.Al2 (SO4) 3. 24H2O]
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30. Which of the following is used to Purify the muddy water? (A) Common salt (B) Potash alum (C) Aluminium Powder (D) Bleaching Powder
(B) [SSC Sec. off 2006] Exp: Potash alum is used for the coagulation of muddy water
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31.Suspended colloidal particles in water can be removed by the process of - (A) Filtration (B) Absorption (C) Adsorption (D) Coagulation
(D) [SSC CHSL 2012] Exp: In water treatment, Coagulation occurs when a coagulant is added to water. Here Potash Alum is added to water to remove Sand, Soil and Colloidal impurities. Alum dissociates into K+, Al3+ and 2- SO4. In this Al3+ coagulate the negatively charged colloidal impurities.
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32.Alum stops bleeding in a minor cut because of- (A) Salvation (B) Emulsion (C) Dialysis (D) Coagulation
(D) [SSC Tax Asst. 2006] Exp: Alum stops bleeding in a minor cut. Its chemical name is potassium aluminum sulphate. It stops bleeding because of coagulation. Blood is a colloid of proteins in water & the K+, Al3+ & 2- SO4 ions coagulate them, causing a blood clot.
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33.Cloud is a colloidal of - (A) Air in a dispersion medium of water (B) Fog in a dispersion medium of water (C) Mist in a dispersion medium of air (D) Water drop in a dispersion medium of air.
(D) [SSC CGL 2005] Exp: Cloud is a colloidal dispersion of water drop in a dispersion medium of air. Cloud consist of small water drops and after some time these drops combined together and condense to form clouds.
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34.An Emulsion is a colloid of a - (A) Gas in a Liquid (B) Liquid in a Liquid (C) Liquid in a Gas (D) Gas in a Solid
(B) [SSC Sec. Off - 2007] Exp: Emulsion is a colloid of a Liquid into a Liquid such as milk, Emulsified oil etc.
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35.Milk is a - (A) Emulsion (B) Suspension (C) Gel (D) Sol
(A) [SSC CHSL 2011] Exp: An emulsion is a suspension of droplets of one liquid into another liquid. Milk is an emulsion of fat in water. Butter is an emulsion of water in fat. The solute is known as the dispersed phase and the solvent is known as the dispersion medium.
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36.A colloidal system in which a Liquid is dispersed in a Liquid is called - (A) Gel (B) Emulsion (C) Sol (D) Precipitate
(B) [SSC CGL 2013] Exp: When a Liquid as disperse phase is mixed in Liquid as dispersion medium then it's known as emulsion eg. Milk.
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37.Which of the following is strongest coagulant? (A) Zinc Chloride (B) Aluminum Chloride (C) Barium Chloride (D) Magnesium Sulphate
(B) Exp: Aluminium chloride is strongest coagulant order of increasing coagulating effect is given as followsNa+ < Mg++ < Al+++, As ionic charge increases, coagulation power increases.
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38.Warming Ammonium chloride with sodium hydrochloride in a test tube is an example of (A) Open system (B) Closed system (C) Isobaric system (D) Isothermal system
(A) (SSC CGL 2016) Exp: Warming ammonium chloride with sodium hydrochloride in a test is an example of open system. A system which can exchange matter as well as energy with the surroundings is called an open system.
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39.An eudiometer measures (A) Atmospheric pressure (B) Time (C) Volume of gases (D) Vapour pressure
(C) (SSC CGL 2016) Exp: An eudiometer was invented by Marsilo Landriani. It is a laboratory device that measures the change in volume of a gas mixture in physical or chemical reaction.
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40.Which of the following is not a donor atom? (A) Phosphorus (B) Antimony (C) Arsenic (D) Aluminium
(D) (SSC CGL 2016) Exp: In semiconductors donor or electron rich impurities are those having five valence electrons for example P, As, Sb, Bi etc. while acceptor or electron deficient impurities are those having three valence electrons example Boron (B), Aluminium (Al) or gallium (Ga).
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41.Which one of the following non-metals shows allotropy in the liquid state? (A) Carbon (B) Sulphur (C) Phosphorous (D) Bromine
(B) (SSC CGL 2016) Exp: A colloidal sol of sulphur is obtained by bubbling H2S gas through the solution of bromine water, sulphurdioxide etc. H2S + Br2 ® 2HBr + S (sol) 2H2S + SO2 2H2O + 3S (sol)
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42.The absolute zero is a temperature at which _________ (A) molecular motion in a gas would cease (B) water freezes (C) all gases become liquid (D) all gases become solid
(A) (SSC CGL 2016) Exp: Absolute zero is the lowest possible temperature at which particles are completely at rest. Zero degree celsius = -273.15 Kelvin.
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43.An emulsion is a colloidal solution of (A) Liquid in liquid (B) Solid in liquid (C) Gas in solid (D) Solid in Solid
(A) (SSC CGL 2016) Exp: An emulsion is a colloidal solution of liquid in liquild. eg. Milk, butter, cold cream, vanishing cream etc. Note: Milk is an emulsion of soluble fats in water.
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44.Which among the following is an example of solid sol? (A) Milk of magnesia (B) Foam (C) Coloured gemstones (D) Rubber
(C) (SSC CGL 2017) Exp: Solid sols are colloidal solution in which solid particles are dispersed in solid dispersion medium. eg:- Coloured gemstones like ruby. Foam is also a colloidal solution in which a gas is dispersed in liquid medium. eg:- Shaving cream.
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45.Which among the following is not an example of emulsion? (A) Chocolate milk (B) Butter (C) Whipped Cream (D) Curd
(D) (SSC CGL 2017) Exp: Emulsions are colloidal solutions in which liquid is dispersed into liquid dispersion medium. eg:- Butter, Chocolate - Milk & Whipped cream.
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46.What is the process of conversion of solid state directly to gaseous state called? (A) Evaporation (B) Condensation (C) Sublimation (D) Distillation
(C) (SSC CGL 2017) Exp: Sublimation is a process in which solid is directly converted into vapour form without going in liquid phase. The substances which show sublimation process, are called as sublimatory substance or sublime. eg:- Iodine, Naphthalene & Camphor etc.
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47.Fog, clouds, mist are examples of _______. (A) Aerosol (B) Solid sol (C) Foam (D) Gel
(A) (SSC CGL 2017) Exp: Aerosol is a colloid of fine solid particles or liquid droplets in air. eg: Fog, cloud, mist. Solid Sol:- It is a colloidal solution in which solid is dispersed in solid dispersion medium eg:- Gemstones like Ruby. Foam:- It is colloidal solution of gas in a liquid or solid. eg: Sponge Gel:- It is colloidal solution of solid dispersed in a liquid or semi-rigid solid. eg:- Gelatin.
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1.Gun Powder is a Mixture of- (A) Sand and TNT (B) TNT and Charcoal (C) Nitrate, Sulphur and Charcoal (D) Sulphur, Sand and Charcoal
(C) [SSC CGL 2008] Exp: Gunpowder is also known as black powder. It is the earliest known chemical explosive. It is a mixture of sulphur, charcoal, and potassium nitrate (saltpeter). The sulphur and charcoal act as fuels, and the saltpeter is an oxidizer.
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2.Which of the following mixture cause the explosion of TNT (Trinitrotoluene) (A) Ammonium Chloride (B) Ammonium Nitrate (C) Ammonium Sulphate (D) Ammonium Nitrite
(B) [SSC MTS 2006] Exp: Mixture of TNT and Ammonium Nitrate forms a highly explosive product is known as Amatol.
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3.Ammonal is a mixture of- (A) Aluminium powder and Ammonium nitrate (B) Aluminium powder and Ammonium chloride (C) Aluminium powder and Ammonium sulphate (D) Aluminium powder and Potassium Nitrate.
(A) [SSC CPO Exam, 2008] Exp: Ammonal is a mixture of Aluminium powder and Ammonium nitrate. Aluminium powder functions as fuel and ammonium nitrate as an oxidizer. Note:- Mixture is affected by humidity because ammonium nitrate is highly hygroscopic.
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4.Trinitrotoluene is (A) used to melt metals (B) used to fuse two metals (C) used as an abrasive (D) used as an explosive
(D) (SSC CGL 2016) Exp: On prolonged heating of Toluene with concentrated Nitric acid & Sulphuric acid, TNT (2, 4, 6 - TrinitroToluene) is formed. It is used as an explosive.
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5.Who discovered cement? (A) Agassit (B) Albertus Magnus (C) Joseph Aspdin (D) Jonseen
(C) [SSC CGL 2010] Exp: Cement is discovered by Joseph Aspdin in 1824. He named his cement Portland
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6.Chemical composition of cement is (A) Limestone and Clay (B) Limestone, Clay and Gypsum (C) Limestone and Gypsum (D) Clay and Gypsum
(B) (SSC CGL 2016) Exp: Raw materials required for the manufacturing of cement are: (i) Limestone (CaCO3) which provides lime (ii) Clay which provides both silica and alumina (iii) Gypsum (CaSO4.2H2O) which decreases setting rate of cement
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7.Cement is formed by strongly heating a mixture of - (A) Lime stone and Graphite (B) Lime Stone and clay (C) Chalk and Graphite (D) Clay and Graphite
(B) [SSC CGL 2011] Exp: Cement is a mixture of compounds like silicates of calcium and aluminates, which are formed by calcium oxide, silica, aluminium oxide and iron oxide. For the formation of cement, limestone and clay mixture is heated at a high temperature in furnace. Then, this mixture is grinded in powdered form with addition of Gypsum and thus the final product is formed, known as Portland cement.
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8.Cement is a mixture of - (A) Calcium Silicate and calcium aluminates (B) Calcium Silicate and Ferrite (C) Calcium aluminates and calcium Ferrite (D) Lime Stone and Silicon dioxide.
(A) [SSC FCI 2012] Exp: Portland cement consists of compounds of lime (calcium oxide, CaO) mixed with silica (silicon dioxide, SiO2) and alumina (aluminium oxide, Al2O3).
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9.Limestone is a raw material used by which industry? (A) Aluminium (B) Fertilizers (C) Cement (D) Petrochemicals
(C) (SSC CGL 2016) Exp: Limestone is a raw material used by cement industry. Other constituents of cement are clay and gypsum.
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10.The process of setting of cement under water is essentially: (A) An oxidation process (B) A reduction process (C) A double decomposition process (D) A hydration process.
(D) Exp: When water is added to cement, cement starts setting. During the setting of cement, hydration of dicalcium silicate (2CaO. SiO3), tricalcium aluminate (3CaO.Al2O3) and tetracalcium aluminate ferrite (4CaO. Al2O3.Fe2O3) occurs & colloidal jelly is formed which starts solidifying.
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11.Setting of cement is: (A) An exothermic reaction (B) An endothermic reaction (C) Neither exothermic nor endothermic (D) None
(A) Exp: Setting of cement is an exothermic process. Hence, cement structures have to be cooled during setting by sprinkling water.
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12.______decreases the rate of setting of cement. (A) Alumina (B) Silica (C) Gypsum (D) Magnesium oxide
(C) (SSC CHSL 2016) Exp: 2 - 3% of gypsum is added to slow down the process of setting of cement and thereby imparting greater strength to it.
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13.The addition of Gypsum to Portland cement helps in- (A) Increasing the strength of cement (B) Rapid setting of cement (C) Preventing rapid setting of cement (D) Reduction in the cost of cement
(C) [SSC CGL 2011] Exp: In Portland cement, Gypsum (CaSO4.2H2O) is added to control the rapid setting of cement.
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14.Concrete is a mixture of: (A) Cement, sand, gravel and water (B) Cement, lime and water (C) Cement, sand and water (D) None
(A) Exp: Concrete is a mixture of cement, sand, gravel and water. This mixture (i.e. concrete) sets in an extremely hard structure and is used in the construction of floors and roofs.
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15.Glass is a - (A) Super Heated Solid (B) Super Cooled Liquid (C) Super Cooled Gas (D) Super heated Liquid
(B) [SSC CGL 2011, SSC Stenographer 2005] or
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What is glass? (A) Super Cooled Liquid (B) Crystalline Solid (C) Liquid Crystal (D) None of these
(A) [SSC MTS 2013, SSC CPO 2011] or Glass is also called (A) Supercooled liquid (B) Super liquid (C) Ideal liquid (D) Distilled liquid (A) (SSC CHSL 2016) Exp: Glass is a non-crystalline solid. It is also known as Super Cooled Liquid because liquid state glass is converted into solid State and Solid State contains it all properties of Liquid State. Simple Glass is a Solid Solution of Silica, Sodium Silicate and Calcium Silicate. Glass is a super cooled Liquid in the form of a non-crystalline solid so it does not have any crystalline Structure and does not have any fixed melting point.
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16.Which one of the following is used for sun glasses? (A) Crookes glass (B) Pyrex glass (C) Crystal glass (D) None of the above
(A) Exp: Crookes glass contain Cerium Oxide(CeO2) which sharply absorbs the U.V rays from the sunlight.
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17.Which type of Glass is used for making glass reinforced plastic? (A) Pyrex glass (B) Quartz glass (C) Flint glass (D) Fibre glass
(D) [SSC CGL Exam, 2011] Exp: Fibre glass is used for making glass reinforced plastic.
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18.Which of the following is responsible for extra strength of Pyrex glass? (A) Potassium carbonate (B) Borax (C) Ferric oxide (D) Lead oxide
(B) Exp: Borax is responsible for extra strength of Pyrex Glass. Borax is used in the manufacturing of Pyrex Glass. Pyrex glass is introduced by Corning Glass Works Company firstly.
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19.Adding which substance gives green colour to glass? (A) Calcium Oxide (B) Iron Oxide (C) Chromium Oxide (D) Manganese Oxide
(C) (SSC CHSL 2016) Exp: Compound Colour Chromium Oxide - Green colour Manganese dioxide - Red Iron (III) Oxide - Brown Cabalt Oxide - Dark blue
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20.Adding which substance gives blue colour to glass? (A) Manganese Oxide (B) Cobalt Oxide (C) Chromium Oxide (D) Iron Oxide
(B) (SSC CHSL 2016) Exp: Compound Colour Chromium Oxide - Green colour Manganese dioxide - Red Iron (III) Oxide - Brown Cabalt Oxide - Dark blue
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21.Which glass is used to make spectacles? (A) Crookes glass (B) Potash glass (C) Jena glass (D) Soda glass
(A) (SSC CHSL 2016) Exp: Crookes glass contains cerium oxide (CeO2) which sharply absorbs the ultraviolet rays from the sunlight so utilised in making spectacles.
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22.______ is used for making chemical apparatus like beakers, flasks etc. (A) Potash glass (B) Hard glass(C) Soda glass (D) Jena glass
(B) (SSC CHSL 2016) Exp: Hard glass or Potash line glass (K2O.CaO.6SiO2):- It is also called Boherian glass. It is mixture of potassium and calcium silicates. It is quite resistant to the action of water and acids. It is used in making chemical apparatus which can withstand high temperature.
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23.The calorie requirement of the body increases in winter as compared to summer because more calories are necessary to- (A) Sustain body temperature (B) Break more proteins (C) Make more fat in the body (D) Compensate for falling hair.
(A) [SSC CPO 2012] Exp: The calories requirement of the body increases in winter as compared to summer because more calories are necessary to sustain body temperature.
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24.Pasteurization is a process in which milk is heated at- (A) At 60°C for 10 min (B) 63°C for 20 min (C) 63°C for 30 min (D) 72°C for 10 min
(C) [SSC Sec off. 2007] Exp: Pasteurization of milk requires about 63°C temperature maintained for 30 minutes or 72°C holding for 15 seconds. This process is used to destroy Mycobacterium tuberculosis and most of the micro organism found in milk.
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25.Combustion is a - (A) Biological Process (B) Physical Process (C) Chemical Process (D) Physical and chemical process
(C) [SSC CGL 2014] Exp: The change which affect the composition as well as chemical properties of matter and result in the formation of a new substance is called a chemical change. These changes are generally irreversible in nature.
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26.Which one of the following fuel causes Least environmental Pollution? (A) Hydrogen (B) Coal (C) Diesel (D) Kerosene
(A) [SSC CPO 2015] Exp: Hydrogen is the least pollution causing fuel. It is used in electro chemical cells and internal combustible engines. It is also used in electric vehicles and electric appliances.
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27.Wheat harvesting is an Example of- (A) Gravity separation (B) Chromatographic separation (C) Fractional distillation (D) Extraction
(A) [SSC Steno 2014] Exp: Wheat harvesting is an example of gravity separation. It is an industrial method of separating two components from their mixture where the constituent particles have different denstites.
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28.Water is not effective in extinguishing a fire caused by petrol because- (A) The Flame is too hot for water to cool it down (B) Water and petrol react chemically (C) Water and petrol are miscible with each other (D) Water and petrol are immiscible with each other and petrol forms upper Layer continue to burn.
(D) [SSC CGL 2008, SSC CHSL 2011] Exp: Water is not effective in extinguishing a fire caused by petrol because water and petrol are immiscible with each other and petrol forms upper Layer continue to burn.
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29.Diesel oil is preferred for heavy motor vehicles because it- (A) It is cheaper (B) Provides less damage to engine (C) It has more capacity and saves fuel. (D) Has large scale production from raw material.
(C) [SSC MTS 2008] Exp: Diesel oil is favourable for Heavy Motor Vehicle because it has more capacity and saves the Fuel.
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30.Quality of Petrol is expressed in terms of - (A) Cetane number (B) Octane number (C) Gold Number (D) None of these
(B) Exp: Quality of petrol is expressed in terms of its octane numbers. It is the measure of ignition quality of fuel. Higher this no. less susceptible is the fuel to knock (explosion caused by its premature buring in the combustion chamber).
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31.Which one of the following is main constituent of LPG? (A) Methane (B) Ethane (C) Propane (D) Butane
(D) [SSC MTS 2011] or
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In LPG cylinder under the high pressure mainly mixture of Gases filled in Liquid form- (A) Methane and Ethane (B)Ethane and Hexane (C) Propane and Butane (D)Hexane and Octane
(C) [SSC Tax Asst. 2007] or Kitchen or Cooking Gas is a mixture of - (A) Methane and Ethylene (B) Carbon dioxide and Oxygen (C) Butane and Propane (D) Carbon Mono oxide and Carbon dioxide (C) [SSC CPO 2010] Exp: LPG (Liquefied Petroleum Gas) is a mixture of Butane (C4H10), Propane (C3H8) and Ethane (C2H6) but its main constituents are butane & propane. Butane is present in more amount as compared to Propane. A powerful Odorant, ethanethiol (C2H5SH; also known as ethyl mercapton) is added so that leaks can be detected easily. Note: Ethyl mercapton is a sulphur compound.
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32.PNG (Piped Natural Gas) is used for - (A) Mining (B) Welding (C) Anaesthesia (D) Cooking
(D) [SSC CGL 2013] Exp: PNG (Piped Natural Gas) is used for cooking. It is a safe fuel. In case of leakage PNG being lighter than air, disperse in the air. It is one of the cleanest burning fuels. When it burns completely, gives out CO2 & water vapour.
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33.Which among the following causes permanent Hardness of water? (A) Magnesium Bicarbonate (B) Sodium Chloride (C) Calcium Sulphate (D) Calcium bicarbonate
(C) [SSC CGL 2014] Exp: Calcium Sulphate causes permanent Hardness of water. It cannot be removed by boiling.Permanent Hardness of water is due to the sulphates of Calcium and Magnesium
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34.Process of removal of calcium and magnesium is known as - (A) Filtration (B) Sedimentation (C) Flocculation (D) Water softening
(D) [SSC Tax Asst. 2009] Exp: Soft water forms lather with soap but hard water does not. The water which does not form lather with soap is known as Hard water. Hardness of water is due to the presence of impurity of bicarbonates, sulphates, chlorides of Calcium and Magnesium. Process of removal of calcium and Magnesium from water is known as water softening.
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35.What is the process of removal of Hardness of water? (A) Purification (B) Filtration (C) Water softening (D) Refining
(C) [SSC MTS 2014] Exp: Water Softening is the removal of calcium, magnesium, and certain other metal cations present in hard water. Water softening is usually achieved by using lime or ion-exchange resins.
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36.Water gas is a mixture of- (A) Carbon monoxide and Hydrogen (B) Carbon monoxide and Nitrogen (C) Carbon dioxide and Nitrogen (D) Carbon dioxide and Nitrogen
(A) [SSC CHSL 2011] Exp: Water gas is a mixture of Carbon monoxide (CO) and Hydrogen (H2)
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37. Water gas constitutes - (A) CO and H2O (B) CO2 and CO (C) CO and H2 (D) CO2 and H2
(C) [SSC CPO Exam, 2015] Exp: Water gas is a mixture of Carbon monoxide and Hydrogen. Mixture of CO and H2 gas is used to synthesise the Methanol it is also known as Syngas.
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37.Which one of the following refer to white soft that covers the land in some areas during the dry Season? (A) Erg (B) Usar (C) Reh (D) Reg
(C) [SSC CGL 2015] Exp: Reh is related to the soluble sodium salts, which covers the some part of land in dry season. It is used as an detergent in rural backward areas.
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38.Detergents used for cleaning clothes and utensils contain- (A) Bicarbonates (B) Nitrates (C) Sulphonates (D) Bismuthates
(C) [SSC MTS 2006, SSC CGL 2005] Exp: A detergent is a special kind of carbon compound, which has cleaning action as same as soap. Detergent can be used in both types of water soft water as well as Hard Water. It mainly Contains sulphonates.
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39.What is the unit of relative density? (A) kg/m (B) kg/m2 (C) kg/m3 (D) It has no unit
(D) (SSC CHSL 2016) Exp: Relative density = Densityof onobject Densityof waterat4ºC = 3 3 kg m kg m / /. Relative density has no unit.
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40.Detergent cleans the surface on the principle of - (A) Viscosity (B) Surface tension (C) Elasticity (D) Buoyancy
(B) [SSC CPO 2008] Exp: Detergent acts on the principle of surface tension. They reduce the surface tension of water.
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41.The Process of Ozonation in water treatment is known as- (A) Ionization (B) Sedimentation (C) Precipitation (D) Disinfection
(D) [SSC CHSL 2012] Exp: Ozone is used in the water treatment for disinfection and oxidation of water. First of all Ozone is used for the treatment of water in Holland in 1893.
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42.Water can be separated from the mixture of water-alcohol by the process of:- (A) Decantation (B) Evaporation (C) Sublimation (D) Distillation
(D) [SSC Tax Asst 2006] Exp: Water can be separated by the mixture of AlcoholWater by the process of Distillation.
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43.Which one of the following substances is highly plastic? (A) Quartz (B) Mica (C) Granite (D) Clay
(D)Exp: The Objects which regain their original configuration completely after removing the deforming force are known as perfectly Elastic body. And the objects which do not regain their original configuration completely and gets permanently deformed are called perfectly Plastic. In real there is no perfectly plastic and no perfectly elastic body, even all object lies between the border line of perfectly elastic and perfectly plastic. But quartz can be taken as perfectly elastic and wax and clay can be considered as perfectly plastic.
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44.Which one of the following is the best fuel in terms of energy released per gram of fuel? (A) Hydrogen (B) Methane (C) Ethanol (D) Butane
(A) [SSC CHSL 2011] Exp: Hydrogen is the best fuel in terms of energy released per gram of fuel. Fuel Energy (Joule/gram) Hydrogen 64186 Methane 55600 Ethanol 30000 Butane (LPG) 49100
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45.An egg sinks in soft water but floats in a concentrated solution of salt water because- (A) Egg absorbs Salt from the solution and expands (B) Albumin dissolves in Salt Solution and egg becomes lighter (C) The Density of Salt Solution exceeds the density of eggs (D) Water has High surface tension.
(C) [SSC CGL 2008] Exp: An Egg sinks in soft water but floats in a concentrated solution of salt because the density of salt solution exceeds the density of egg.
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46.Which one of the following Liquid has least density? (A) Clean water (B) Salt water (C) Petrol (D) Mercury
(C) [SSC PO 2009] Exp: From the given options petrol has least density. Liquid Clean water Salt water Petrol Mercury Density 1.00 1.03 0.71 13.53 (gm/cm3)
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47.Impure camphor is purified by the process of:- (A) Sublimation (B) Filtration (C) Sedimentation (D) Evaporation
(A) [SSC CPO 2006] Exp: Sublimation is the process in which solid directly changes into gaseous state, without forming any liquid state. Camphor, Iodine & Naphthalene are Sublimatory substance.
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48.Which one of the following is not a mixture- (A) Air (B) LPG (C) Gasoline (D) Distilled water
(D) [SSC DEO 2009] Exp: Distilled water is the purest form of water, while air, gasoline and LPG are mixtures.
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49.When water itself combines chemically with some element or mineral it is called- (A) Carbonation (B) Desalination (C) Oxidation (D) Hydration
(D) [SSC CHSL 2012] Exp: When water itself combines chemically with some element or mineral then it is known as Hydration.
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50.Iodine can be separated from a mixture of Iodine and potassium chloride by- (A) Filtration (B) Sublimation (C) Distillation (D) Sedimentation
(B) [SSC CHSL 2010] Exp: Iodine can be separated from a mixture of Iodine and potassium chloride by the process of sublimation.
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51.What is the fourth State of Matter? (A) Gas (B) Vapour (C) Plasma (D) Electron
(C) [SSC CGL 2005] Exp: There are mainly three states of matter solid, Liquid and Gas, but fourth state is known as Plasma (colloidal form).
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52.Spirit in contact with body gives cool sensation because it is - (A) A Liquid (B) A conductor (C) A transparent (D) Highly volatile
(D) [SSC Steno- 2010] Exp: Spirit gives cooling sensation in contact with body because it is highly volatile and evaporates the water from body and takes out some heat of the body.
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53.A Liquid is said to be boiled when its- (A) Vapour pressure becomes zero. (B) Vapour pressure is greater than the surrounding pressure. (C) Vapour pressure is less than the surrounding pressure. (D) Vapour pressure is equal to the surrounding pressure.
(D) [SSC CPO 2012] Exp: A Liquid starts boiling when its vapour pressure becomes equal to the surrounding pressure.
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54.Hygroscopic objects are those which instantly absorb- (A) Hydrogen sulphide (B) Carbon monoxide (C) Ammonia (D) Water vapours
(D) [SSC MTS 2014] Exp: Hygroscopic substances are those which absorb humidity (water vapours) from their surrounding instantly such as Sugar, Honey, Ethanol etc.
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55.Quantity (Amount) of water vapours present in atmosphere is measured in - (A) In the form of Humidity (B) In the form of Smog and Fog(C) In the form of Nodes (D) All of these
(A) [SSC FCI 2012] Exp: Humidity is the amount of water vapours present in the atmosphere.
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57. The Physical method Commonly used to purify Sea water is- (A) Filtration (B) Evaporation (C) Sedimentation (D) Distillation
(D) [SSC Steno 2012] Exp: Distillation method is used commonly to purify sea water.
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51.Sea water can be purified by the process of- (A) Distillation (B) Evaporation (C) Filteration (D) Fractional distillation
(A) [SSC CPO 2008] Exp: Distillation is a process of separating the component from a liquid mixture by selective evaporation and condensation.
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52.Which of the following Statements is not true regarding covalent compounds? (A) Compounds are generally Liquids and Gases (B) Melting and Boiling points are low (C) Slow reaction (D) Fast Reaction.
(D) [SSC CPO 2012] Exp: Covalent compounds have following Characteristics:- 1. Compounds are generally Liquids and Gases. 2. Compounds have low Melting points and Boiling point 3. Reaction takes place at very slow rate.
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53.Nitrolim is prepared by heating: (A) CaO with N2 (B) CaO with O2 (C) CaC2 with N2 (D) CaC2 with O2
(C) Exp: Nitrolim is mixture of Calcium cyanamide (CaCN2) and carbon and is prepared by heating CaC2 in an atmosphere of N2. CaC2 + N2 2 Nitrolim CaCN C
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54.The lighting bolts in the atmosphere cause the formation of: (A) NO (B) NH3 (C) NH4OH (D) NH2OH
(A) Exp: During the lighting bolts, atmospheric N2 and O2 combine together to form NO. 2 2 From atomosphere N O During ligh ting bolts 2NO -
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55.Which compound of lead is used as antiknocking agent? (A) Lead tetra acetate (B) Basic lead sulphate (C) Tetraethyl lead (D) Sublimed white lead
(C) Exp: CO is produced in the atmosphere due to the incomplete combustion of petrol in the internal engine of automobiles. Thus the automobiles exhaust contains CO which makes the the air polluted. In order to minimise air pollution caused by CO, tetraethyl lead, (C2H5) 4 Pb is mixed with petrol. This compound provides more time to the petrol for its combustion and hence makes the petrol to burn at slow speed or more completely. Due to the slow burning of petrol, the quantity of CO released by the automobiles is decreased and hence pollution of air caused by CO is also minimised.
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56.Hypo is used in photography for: (A) Developing picture (B) Picture printing (C) Colouring picture (D) The fixation of picture.
(D) Exp: Hypo is used in photography as a fixer, i.e. for fixing the picture.
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57.Silver salt used in photography is? (A) AgCl (B) AgNO3 (C) AgF (D) AgBr
(D) Exp: Out of the given salts of Ag, AgBr is the most sensitive compound to light and hence undergoes photo reduction to metallic Ag on exposure of light. 2AgBr Light(h) 2Ag+Br
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58.Sodium thiosulphate is used in photography because of its: (A) Oxidising behaviour (B) Reducing behaviour (C) Complexing behaviour (D) Photo chemical behaviour
(C) Exp: Because of complexing behaviour of sodium thiosulphate (Na2S2O3), this salt dissolves the unreacted AgBr as soluble complex compound, Na3[Ag(S2O3) 2] and thus fixes the image. AgBr + 2Na2S2O3 Na3[Ag(S2O3) 2]+NaBr
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66. Fluid commonly used for making Bio-gas - (A) Animal Waste (B) Aquatic Plants (C) Plant waste (D) None of these
(A) [SSC FCI 2012] Exp: Biogas can be produced by anaerobic digestion or fermentation of animal waste. It is a renewable source of energy.
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67.Gobargas mainly contains - or Main constituent of biogas is- (A) Carbon monoxide (B) Carbon dioxide (C) Hydrogen sulphide (D) Methane
(D)Exp: The average composition of biogas is: (i) CH4 (Methane) = 50 - 60% (ii) CO2 = 32 - 40% (iii) H2 = 5 - 10% (iv) N2 = 2 - 6% (v) H2S = small amount constituent Out of these, the constituent methane (an extremely good fuel) makes biogas as an excellent fuel.
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68.Burning of candle is a - (A) Photo chemical reaction (B) Physical change (C) Exothermic reaction (D) Endothermic reaction
(C) [SSC MTS 2014] Exp: Burning of Candle is an exothermic reaction. Heat is evolved in Exothermic reactions. It is possible when the energy of reactants is more than the energy of products.
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69.Paper is made by- (A) Cellulose of plants (B) Plants flower (C) Fruit Juice (D) Proteins of Plants
(A) [SSC FCI 2012] Exp: Paper is made from raw material called pulp. Cotton fibres are used for paper making. Paper is made by cellulose of plants
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70.Which one of the following element is used in the manufacturing of Fertilizers? (A) Potassium (B) Aluminium (C) Lead (D) Fluorine
(A) [SSC MTS 2011] Exp: Potassium element is used in the manufacturing of fertilizers. Fertilizer having potassium known as Potash Fertilizers. eg:- Potassium chloride, Potassium nitrate, Potassium sulphate etc.
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71.Select the correct statement. (A) Mixtures are homogeneous. (B) In a mixture the components are present in a fixed ratio. (C) The component of a mixture cannot be separated. (D) The properties of a mixture are same as that of its component.
(D) [SSC CPO 2012] Exp: Mixture is a material containing two or more substances either elements or compounds or both in any proportion. A mixture refers to the only physical combination (not chemical combination) of substances in which each substance retains its own chemical identity. There are two types of mixture- Homogenous and Heterogenous. The components of mixtures can be separated by following methods:- Filtration, Sublimation, Distillation, Magnetic separation, Solvent Extraction etc.
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72.What is the main source of manufacturing of Nitrogenous Fertilizer? (A) Ammonia (B) Nitrogen (C) Nitric acid (D) Nitrogen dioxide
(A) Exp: Ammonia is the main source of manufacturing of Nitrogenous fertilizer. It is prepared by Haber's process. N2+3H2 Fe,Mo 2NH3.
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73.Which among the following does not contain Nitrogen element? (A) Urea (B) Super phosphate of Lime (C) Indian Salt Shora (D) Chile Salt Shora
(B) [SSC MTS 2013] Exp: Super phosphate of lime Ca(H2PO4) 2 is a phosphorus fertilizer so it does not contain Nitrogen element while others have Nitrogen element.
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74.Too much baked edible oils should not be used repeatedly (A) The oil vapour can cause indoor pollution (B) Carcinogenic substances like benzopyrene are produced. (C) Nutrient value of food is lost (D) Loss and wastage of oil.
(B) Exp: Edible oil contains carcinogenic substances such as Benzopyrene, which can cause cancer. So, edible oils should not be used repeatedly.
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75.What happens when a drop of Glycerol is added to KMnO4 spread on paper? (A) There is violent explosion (B) There is a crackling sound (C) The paper ignites (D) There is no reaction
(C) [SSC CGL 2015] Exp: When a drop of glycerol is added to KMnO4 spread on paper, and then paper ignites. KMnO4 act as a strong oxidant.
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76.Concentration of a material which is Lethal to 50% animal is called as - (A) LD50 (B) LC50 (C) NOAEL (D) ADI
(B) [SSC CHSL Exam, 2014] Exp: The concentrations of the material (chemicals) in air that kills 50% of the test animals during the observation period, is called as the LC50 value.
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77.Non-Metal found in Liquid state is - (A) Bromine (B) Nitrogen (C) Fluorine (D) Chlorine
(A) [SSC CHSL 2013] Exp: Bromine is the only non-metal which is found in liquid state at normal temperature.
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78.Which of the following is not a chemical change? (A) Burning of paper (B) Digestion of food (C) Conversion of water into steam (D) Burning of coal
(C)Exp: Conversion of water into steam is a physical change. Because it is a physical change and it is reversible process. So water can be obtained again from this steam.
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79.Which of the following contains high content of Lead? (A) Cool (B) Cooking Gas (C) High octane fuel (D) Low octane fuel
(C) [SSC CPO Exam, 2011] Exp: High octane fuel contains high amount of Lead.
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80.The effect or response produced by two or more chemicals are less than the sum of the effects or response that the chemical would produce individually known as - (A) Antagonism (B) Independent (C) Additive (D) Synergism
(A) [SSC CGL 2013] Exp: In chemistry, Antagonism is a phenomenon wherein two or more agents in combination have an overall effect that is less than the sum of their individual effects.
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81.Water does not evaporate, if- (A) Temperature is Less than 00C (B) Humidity is 0% (C) Humidity is 100% (D) Temperature is 1000C
(C) [SSC Stenographer 2011] Exp: If Humidity is 100% in atmosphere, then water will not boil because amount of water vapours in atmosphere reaches to its maximum value and possibility of evaporation becomes zero.
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82.The amount of chlorine available in water after disinfection called as - (A) Free Chlorine (B) Residual chlorine (C) Free available chlorine (D) Combined available chlorine
(B) [SSC Tax Asst. 2008] Exp: Amount of chlorine available in water after disinfection is called Residual chlorine
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83.The mass of 10 moles of water is- (A) 18g (B) 180g (C) 90g (D) 45g
(B) [SSC CGL 2012] Exp: Mass of 1 mole of water is 18g, H2O = 1 × 2 + 16 = 18g \ mass 10 mole of water = 10 × 18 = 180g
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84.When pressure is increased, the boiling point of water (A) Decreases (B) Increases (C) Remains same (D) Depends
(B) Exp: The temperature at which a substance boils is known as its boiling point. On increasing pressure boiling point of substance increases.
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85.What is the fundamental unit of amount of a substance? (A) Mole (B) Candela (C) Kelvin (D) Meter
(A) (SSC CHSL 2016) Exp: No. of moles = Givenmassof substance Molecularmassof substance
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86.______is the major component of natural gas. (A) Acetone (B) Methane (C) Chlorine (D) Hexane
(B) (SSC CHSL 2016) Exp: Natural gas is a fossil fuel contains mixtures of hydrocarbons. Methane is main component of natural gas.
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87.Which among the following is not a characteristic of transition metals? (A) Tendency to gain electrons (B) Low electronegativity (C) Low ionization energy (D) Malleability
(A) (SSC CHSL 2016) Exp: Metals are electropositive in nature i.e. metals have tendency to loose electrons not to gain electrons.
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88.The conversion of hard water into soft water by boiling or adding calcium hydroxide is called _______. (A) Baker's process (B) Temp's process (C) Clarke's process (D) Lake's process
(C) (SSC CHSL 2016) Exp: Clarke's method is used to convert hard water into soft water. In this method calculated amount of lime is added to hard water. It precipitates out Calcium Carbonate and Magnesium Hydroxide which can be filtered off.
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89.What is the Greenhouse Effect? (A) The fall in population of plants due to human activity (B) It is the warming of earth's surface due to its atmosphere (C) The polluting effect of burning fossil fuels (D) The heating of the atmosphere due to depletion of the ozone layer
(B) (SSC CHSL 2016) Exp: Green house effect means trapping of solar energy due to atmospheric gases. CO2, CH4, CFC, N2O are green house gases. The warming of earth's surface due to the trapping of infrared radiations reflected from the earth's surface by CO2 layer in the atmosphere is called green house effect.
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90.Which chemical is used to ripe mangoes artificially? (A) Sulphur Dioxide (B) Nitrous Oxide (C) Calcium Carbide (D) Phosphorous
(C) (SSC CHSL 2016) Exp: Calcium carbide is used to ripe mangoes artificially. Calcium carbide produce acetylene gas which acts as the natural ripening agent.
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91.For what is Mohs scale used? (A) To measure brightness of a substance (B) To measure viscosity of a liquid (C) To measure elasticity of a material (D) To measure hardness of minerals
(D) (SSC CHSL 2016) Exp: Mohs scale is used to measure the relative hardness of minerals. It characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material. Some minerals and their hardners is given below. Minerals Hardness Talc 1 Gypsum 2 Quartz 7 Topaz 8 Corundum 9 Diamond 10
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92.Name the international treaty designed to protect the Ozone layer from CFCs. (A) Sigma protocol (B) Montreal protocol (C) Ozone protocol (D) Green protocol
(B) (SSC CHSL 2016) Exp: The Montreal Protocol (1987) is a global agreement to protect the Ozone layer by phasing out the production and consumption of ozone depleting substances (ODS).
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93.Which of the following is an effective Fire Extinguisher? (A) Argon (B) Halons (C) Halogen (D) Helium
(B) (SSC CHSL 2016) Exp: Halons are effective fire extinguisher. Halons are a family of chemicals similar to chlorofluoro carbons (CFCS), but containing at least one atom of bromine. Halons are also part of a group of chemicals known as the volatile organic compounds.
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94.Who Invented Laser? (A) William Friese Greene (B) Arthur Fry (C) Gordon Gould (D) Otto von Guericke
(C) (SSC CHSL 2016) Exp: Laser was invented by Gordon Gould.
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95. Who Invented LED? (A) Nick Holonyak (B) Elias Howe (C) Chuck Hull (D) Christiaan Huygens
(A) (SSC CHSL 2016) Exp: LED refers to light emitting diode. LED was invented by Nick Holonyak.
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95.What is dehydration? (A) Removal of acid from a molecule (B) Removal of base from a molecule (C) Removal of water from a molecule (D) Removal of alkali from a molecule
(C) (SSC CHSL 2016) Exp: Dehydration reactions can be defined as the removal of water molecules from the reacting molecules. Note: Sulphuric acid is a strong dehydrating agent.
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96.Which is the most economical method of removing solid matter from water? (A) Using deactivated carbon (B) Electrolysis (C) Distillation (D) Sedimentation
(D) (SSC CHSL 2016) Exp: Sedimentation is the most economical method of removing solid matter from water.
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97.Nitrogen fixation is a process of (A) Assimilation of nitrate (B) Utilisation of nitrogen gas (C) Conversion of organic nitrogen into proteins (D) Conversion of molecular nitrogen into ammonia
(D) (SSC CGL 2016) Exp: Nitrogen fixation is a process of conversion of molecular nitrogen into ammonia or other molecules available for living organism.
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98.A hard coal containing little volatile matter is called ______. (A) Loess (B) Anthracite (C) Atoll (D) Lava
(B) (SSC CHSL 2016) Exp: Anthracite coal is also known as Hard coal. It contains 92-98% Carbon and little volatile matter.
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99.Who invented Aerosol can? (A) Erik Rotheim (B) Erik Mathew (C) Erik Tim (D) Eric Flayer
(A) (SSC CHSL 2016) Exp: Aerosol spray can was invented in 1926 Eric Rotheim from Norway.
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100.What is the chemical formula of aluminium nitride? (A) AlN (B) Al2N (C) AlN2 (D) AlN2
(A) (SSC CHSL 2016) Exp: Aluminiumion = Al3+ Nitride ion = N3- So, chemical formula of Aluminium Nitride will be AlN.
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101.The upper part of the heterosphere is composed almost completely of which gas? (A) Ozone (B) Nitrogen (C) Oxygen (D) Hydrogen
(D) (SSC CHSL 2016) Exp: Heterosphere lies above the homosphere, on average heterosphere begins at an altitude of about 80 km. In the heterosphere the concentration of the heavier gases such as nitrogen or oxygen decreases more rapidly with increasing altitudes. Hydrogen gas concentration is high.
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102._______ is an anaesthetic agent. (A) Acetylene (B) Glycol (C) Diethylether (D) Ethylene
(C)Exp: Diethylether (ether) is used as anaesthetic agent used in surgery. However, now a days better compounds like enflurane and isoflurane are available.
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103.The boiling point of liquids vary as (A) Pressure varies (B) Temperature varies (C) Volume varies (D) Density varies
(A) (SSC CGL 2016) Exp: Boiling point of liquid is the temperature at which its vapour pressure of liquid is equal to the pressure of the air. Boiling point depends on pressure.
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104.At boiling point of liquids, its (A) Temperature increases (B) Atmospheric pressure increases (C) Temperature remains constant (D) Vapour pressure decreases
(C) (SSC CGL 2016) Exp: Temperature remains constant during the boiling of water even though heat is supplied continuously. This is because, the heat supplied is absorbed by water molecules and this heat increases their kinetic energy.
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105.The biogas used for cooking is a mixture of which of the following? (A) Carbon dioxide & oxygen (B) Isobutane& propane (C) Methane & Carbon monoxide (D) Methane & Carbon dioxide
(D) (SSC CGL 2016) Exp: The biogas used for cooking is a mixture of Methane & Carbon dioxide.
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106.Biofertilizers convert nitrogen to_______. (A) Nitrates (B) Ammonia (C) Nitrogenase (D) Amino acids
(B) (SSC CGL 2016) Exp: Biofertilizers are micro organism which bring about nutrient enrichment of soil by enhancing the availability of nutrients to crop. Biofertilizers convert nitrogen to ammonia by the nitrogen fixation process.
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107.Which of the following State has become India's first carbon free State? (A) Himachal Pradesh (B) Madhya Pradesh (C) Uttar Pradesh (D) Maharashtra
(A) (SSC CGL 2016) Exp: Himachal Pradesh State has become India's first carbon free State.
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108.Calcium salts which is used as fertilizer:- (A) Calcium Carbide (B) Calcium Carbonate (C) Calcium Cyanide (D) Calcium Sulphate
(D) (SSC CGL 2016) Exp: Calcium Sulphate (Gypsum) is listed as inorganic fertilizer. It is used to improve soil quality.
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109.Sea water is saltier than rain water because (A) Sea animals are salt producing (B) The air around the sea is saltish (C) Rivers wash away salts from earth and pour them into the sea (D) Sea beds have salt producing mines
(C) (SSC CGL 2016) Exp: Sea water is Saltier than rain water because it contains large amount of the salt, sodium chloride. Salts are brought to the sea through many sources like rivers and streams which collect various minerals, salts and silt on their course and drain them into the Oce
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110.Which one of the following is not a nonconventional source of energy? (A) Solar Energy (B) Natural Gas (C) Wind Energy (D) Tidal Power
(B) (SSC CGL 2016) Exp: Non-conventional energy sources are those sources that are renewable, infinite and restorable. For example, Wind energy, tidal energy, solar energy.
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111.Nitrification is the biological process of converting (A) N2 into nitrate (B) N2 into nitrite (C) Ammonia into nitrite (D) Ammonia into N2
(C) (SSC CGL 2016) Exp: Nitrification is an important step in the nitrogen cycle in soil. In this process ammonia (NH3) or Ammonium ion (NH4 +) is converted to nitrite ion (NO2 -) and then nitrate ion (NO3 -) by bacteria. For eg. Nitrosomonas.
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112.Which of the following produces the most solid waste? (A) Agriculture (B) Power Plants (C) Manufacturing Industry (D) Packaging Industry
(C) (SSC CGL 2016) Exp: Manufacturing industry produces the most solid waste.
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113.Spraying of DDT on crops causes pollution of __________. (A) Air & Soil (B) Crops & Air (C) Soil & Water (D) Air & Water
(C) (SSC CGL 2016) Exp: Spraying of DDT on a crops causes pollution of soil and water. DDT has an extremely low volatility and may be the least soluble chemical known which makes it extremely persistent in soils and aquatic sediments.
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114.The waste management technique that involves the use of micro-organisms to remove or neutralize pollutants from contaminated site is called (A) Bio sensor (B) Bio magnification (C) Bio remediation (D) Bio concentration
(C) (SSC CGL 2016) Exp: Bioremediation is a waste management technique that involves the use of micro-organism to remove or neutralize pollutants from contaminated site.
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115.The source of energy that causes the least global warming is (A) coal (B) Geothermal energy(C) Natural Gas (D) Petroleum
(B) (SSC CGL 2016) Exp: In the given options Geothermal energy causes the least global warming.
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116.Which of the following is a commercial source of energy? (A) Agricultural waste (B) Dried dung (C) Sun (D) Natural gas
(D) (SSC CGL 2016) Exp: The sources of energy that are available to the users at economic price are referred as commercial energy. For example: Coal, Petroleum, natural gas and electricity. These are generally exhaustible
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117.Honey that has high concentration of sugar does not decay because (A) Bacteria cannot survive in an active state as it is totally deprived of oxygen (B) It contains natural antioxidant that prevents bacterial attack (C) Bacteria cannot survive in an active state in a solution of high osmotic strength as water is drawn out (D) None of these
(C) (SSC CGL 2016 Exp: Honey that has high concentration of sugar does not decay because bacteria cannot survive in an active state in a solution of high osmotic strength as water is drawn out.
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118.At low temperature, Lead behaves as a: (A) Semi conductor (B) Super conductor (C) Insulator (D) Conductor
(B) (SSC CGL 2016) Exp: At low temperature, Lead behaves as a super conductor. Superconductivity was discovered by Kamerlingh onnes on April 8, 1911. It is the ability of certain materials to conduct electric current with practically zero resistance.
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119.Precipitation in the form of a mixture of rain and snow is called (A) Drizzle (B) Hail (C) Sleet (D) Snow
(C) (SSC CGL 2016) Exp: Sleet (Rain and snow mixed) is precipitation composed of rain and partially melted snow. This can occur where the temperature in the lower part of atmosphere is slightly above the freezing point (0ºC or 32ºF)
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120.The elements known as primary nutrients for plants (A) Nitrogen, Phosphorus and Potassium (B) Nitrogen, Oxygen and Silicon (C) Potassium, Boron and Nitrogen (D) Nitrogen, Phosphorus and Iron
(A) (SSC CGL 2016) Exp: The elements used as primary nutrients for plants are nitrogen, phosphorous and potassium.
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121.Which of the following sources has the largest share in power generation in India? (A) Atomic power (B) Thermal power (C) Hydro power (D) Wind power
(B) (SSC CGL 2016) Exp: Thermal power plant is the largest source of power in India. About 71% of electricity consumed in India are generated by thermal power plants. Thermal power plants are based on fuel such as coal, gas and diesel.
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122.Iron and manganese present as pollutants in water cannot be removed by________. (A) Oxidation followed by setting and filtration (B) Chlorination (C) Ion exchange process (D) Lime soda process or manganese zeolite process
(B) (SSC CGL 2016) Exp: Iron and managanese present as pollutants in water can not be removed by chlorination. Chlorination is the process of adding chlorine in water to kill certain bacteria and microbes.
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123.Which is the first Indian State to go wholly organic? (A) Meghalaya (B) Sikkim (C) Manipur (D) Assam
(B) (SSC CGL 2016) Exp: Sikkim is the first Indian State to go wholly organic.
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124.What is the source of natural energy of the hot springs at Manikaran in Himachal Pradesh? (A) Geo Thermal Energy (B) Biomass Energy (C) Thermal Energy (D) Hydro Energy
(A) (SSC CGL 2016) Exp: When underground water comes in the contact of hot rocks. It changes to steam and is trapped between the rocks. Sometimes steam gets some outlets on the surface and comes out. They are called Hot springs.
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125.Which State of India is leading in solar energy generation? (A) Gujarat (B) Rajasthan (C) Haryana (D) Uttar Pradesh
(B) (SSC CGL 2016) Exp: Rajasthan State of India is leading in solar energy generation.
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126.Which of the following is not a commercial source of energy? (A) Coal (B) Petroleum (C) Natural Gas (D) Firewood
(D) (SSC CGL 2016) Exp: Firewood is not a commercial source of energy.
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127.Removal of carbon particles from air involves the principle of (A) Precipitation (B) Filtration (C) Electrophoresis (D) Sedimentation
(C)Exp: Removal of carbon particles from air involves the principle of Electrophoresis. Colloidial particles are electrically charged. When an electric current is passed through the colloidal solution, the particles move towards a particular electrode. This is termed Electrophoresis or Cataphoresis.
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128.Which one of the following is commonly used for pulp bleaching in the paper industry? (A) Mild sulphuric acid (B) Glucose isomerase (C) Hydrogen peroxide (D) Iodine and water
(C) (SSC CGL 2016) Exp: Hydrogen peroxide act as a bleaching agent due to the release of nascent oxygen. H2O2 H2O + [O] Thus bleaching action of H2O2 is permanent and is due to oxidation. It oxidises the colouring matter to a colourless product. Colouring matter + [O] Colourless matter.
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129.Ozone protects biosphere from (A) X-rays (B) Gamma rays (C) Ultraviolet rays (D) Infrared rays
(C) (SSC CGL 2016) Exp: Ozone layer of the stratosphere absorbs UV rays. Hence it acts as shield against UV rays.
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130.The molecular mass of a gas is (A) Twice its vapour pressure (B) Equal to its vapour pressure (C) Half its vapour pressure (D) Not related to its vapour pressure
(A) (SSC CGL 2016) Exp: Vapour density = Relative molecular mass 2 so relative molecular mass is the twice of vapour density.
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131.Brown stains in vessels and clothes indicate the presence of high quantities of_________in Water (A) Magnesium (B) Calcium (C) Manganese (D) Chromium
(C) (SSC CGL 2016) Exp: Manganese is typically found in iron-bearing water. Manganese produce brownish black stain. Soap and detergents do not remove stains, and use of chlorine bleach may intensify the stains.
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132.In water treatment plant, use of chloramines ensures _________ (A) Taste and odour control (B) Weed control in reservoirs (C) Disinfection (D) Removal of permanent hardness
(C) (SSC CGL 2016) Exp: Chloramines are chemical compounds that contain chlorine and ammonia. Adding of chloramine to water to disinfect water is known as Chlorination.
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133.Super cooling stands for cooling of a liquid: (A) At freezing point (B) Below freezing point (C) At melting point (D) Above melting point
(B) (SSC CGL 2016) Exp: Supercooling is the process of cooling or chilling of liquid or gas below its freezing point without crystallization or solidification. It is also known as Undercooling.
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134.A lcohol is more volati le than water because__________is lower than water (A) Its boiling point (B) Its density (C) Its viscosity (D) Its surface tension
(A) (SSC CGL 2016) Exp: Alcohol is more volatile than water because its boiling point is lower than water.
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135.Which method will be employed to test the hardness of water? (A) Boiling (B) Distillation (C) Formation of lather with soap (D) None of these
(C) (SSC CGL 2016) Exp: Water which does not produce lather with soap solution readily is called Hard water. eg. river water, well water, sea water and tap water.Hardness of water is due to the presence of the bicarbonates, chlorides and sulphates of Calcium and Magnesium
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136.Biuret test is not given by (A) Proteins (B) Carboydrate (C) Polypeptides (D) Urea
(B) Exp: Biuret test is the characteristic test for the amide linkage since there is no amide linkage in carbohydrates, they do not give this test.
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138. Absolute Zero is defined as (A) The temperature at which all molecular motion ceases (B) At which water boils at 298K (C) At which liquid Helium boils (D) At which the volume becomes zero
(A) (SSC CGL 2016) Exp: Absolute Zero is defined as the temperature at which all molecular motion ceases. It is 0 kelvin (-273.15°C).
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139.Which of the following is used for the preparation of dynamite? (A) Methyl alcohol (B) Iron oxide (C) Nitro Glycerol (D) Copper sulphate
(C) (SSC CPO 2017) Exp: Nitro Glycerol or Nitro glycerin is used for the preparation of dynamite. Nitroglycerol acts as an explosive in dynamite, which is used for mining purpose.
250
140. Which of the following drug is used to get pain relief in muscles? (A) Analgesics (B) Antibiotic (C) Antiseptics (D) Antidotes
(A)Exp: Analgesics :- These are drugs, which give relief from pain on ingestion. Antibiotic :- Drugs used in the treatment & prevention of bacterial infections. Antiseptics :- Antimicrobial substances which are applied to living tissue to reduce the probability of infection. Antidotes :- Substance which can counteract the effect of poisoning.
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140.Which of the following is an example of sublimation? I. Dry ice II. Camphor III. Ice (A) I and II (B) I, II and III (C) Only I (D) Only II
(A) (SSC CPO 2017) Exp: Sublimation is the process in which solid substance is directly converted into vapour form. The substances which directly convert from solid state to vapour form, are called as sublimatory substances or sublime. eg: Iodine, Camphor, Dry ice, Naphthalene etc.
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141.Which of the following is not a transition metal? (A) Actinium (B) Bohrium (C) Osmium (D) Radium
(D) (SSC CPO 2017) Exp: Transition elements are d block elements. Actinium, Bohrium & Osmium are d block elements. Radium belongs to s block (Alkaline Earth Metals).
253
142.Which of the following is not a characteristic of a solid? (A) High compressibility (B) High density (C) Regular shape (D) High rigidity
(A) (SSC CPO 2017) Exp: Solids have high density, regular shape & rigid in nature due to strong intermolecular force & negligible intermolecular distance. Solids can not be compressed. They have negligible compressibility. Gases have high compressibility as there is a large intermolecular distance.
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143.Who among the following is not a recipient of Nobel Prize 2016 in the field of Chemistry? (A) Jean - Pierre Sauvage(B) Sir J. Fraser Stoddart (C) Bernard L. Feringa (D) John M. Kosterlitz
(D) (SSC CPO 2017) Exp: The Nobel Prize in Chemistry 2016 was awarded jointly to Jean - Pierre Sauvage, Sir J. Fraser Stoddart & Bernard L. Feringa for the design & synthesis of molecular machines.
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144.Which of the following cloth will readily catch fire? (A) Cotton cloth (B) Polyester cloth (C) Acrylic cloth (D) Nylon cloth
(A) (SSC CPO 2017) Exp: Cotton cloth catches fire easily because of its light texture.
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145.Which of the following has least melting point? (A) Carbon (B) Silver (C) Mercury (D) Gold
(C) (SSC CPO 2017) Exp: Mercury is found in liquid state at room temperature while silver, carbon & gold are solid. As mercury is present in liquid state, its melting point is low.
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146.Who discovered X-rays? (A) W. C. Roentgen (B) Albert Einstein (C) Samuel Cohen (D) Edward Taylor
(A) (SSC CGL 2017) Exp: Wilhelm Conrad Roentgen, a german professor of physics discovered X-rays in 1895.
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147.Which of the following are highly compressible? (A) Solid (B) Liquid (C) Gas (D) Solid and Liquid
(C) (SSC CGL 2017) Exp: Gases are highly compressible due to presence of large intermolecular distance & very small intermolecular force. Compressibility order:- Gases > Liquids > Solids (negligible)
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148.Which of the following gases is heavier than oxygen? (A) Carbon dioxide (B) Ammonia (C) Methane (D) Helium
(A) (SSC CGL 2017) Exp: Mass of Oxygen O2 = 2 × 16 = 32g Mass of Carbon Dioxide CO2 = 12 + 2 × 16 = 44g Mass of Ammonia NH3 = 14 + 3 × 1 = 17g Mass of Methane CH4 = 12 + 4 × 1 = 16g Mass of Helium He = 4g Mass of CO2 is greater than the mass of oxygen. So, CO2 is heavier than oxygen.
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149.Ozone is an ______ of oxygen. (A) Allotrope (B) Isotope (C) Isobar (D) Isotones
(A) (SSC CGL 2017) Exp: When an element exists in different physical forms in nature. This phenomenon is called Allotropism, & different forms are called as allotropes. eg: Ozone is an allotrope of Oxygen. Diamond, Graphite & Fullerene are allotropes of carbon.
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150.Which of the following gas was released during Bhopal gas tragedy? (A) Methyl isocyanate (B) Sodium isothiocyanate (C) Nitrogen isothiocyanate (D) Potassium isothiocyanate
(A) (SSC CGL 2017) Exp: Bhopal gas tragedy was caused by (MIC) methyl isocyanate (CH3NCO) on December 2, 1984 in Bhopal (M.P) in the Union Carbide factory. MIC is used for manufacturing the insecticide, Carbaryl.
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151.Which of the following is not an example of Allotrope? (A) Diamond (B) Graphite (C) Ozone (D) Steel
(D) (SSC CGL 2017) Exp: When an element exists in different physical forms in nature. This phenomenon is called Allotropism, & different forms are called as allotropes. eg: Ozone is an allotrope of Oxygen. Diamond, Graphite & Fullerene are allotropes of carbon.
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152.Supercooling is cooling of liquid _____. (A) Below melting point (B) Below freezing point (C) At melting point (D) Above melting point
(B) (SSC CGL 2017) Exp: Supercooling is a cooling of liquid below freezing point.
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153.The process of melting is also called as:- (A) Fusion (B) Galvanisation (C) Crystallisation (D) Evaporation
(A) (SSC CGL 2017) Exp: The process of melting is also called as fusion. Solid Fusion Liquid
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154.Who discovered Potassium? (A) Humphry Davy (B) Alan Turing (C) Bill Gates (D) Tim Berners-Lee
(A) (SSC CGL 2017) Exp: Potassium was isolated by Humphry Davy in 1807 through the electrolysis of molten caustic potash (KOH).
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155.Who is not amongst the winners of Nobel Prize 2016 for Chemistry? (A) Jean-Pierre Sauvage (B) J. Michael Kosterlitz (C) Sir J. Fraser Stoddart (D) Bernard L. Feringa
(B) (SSC CGL 2017) Exp: Jean-Pierre Sauvage, Sir J. Fraser Stoddart and Bernard L. Feringa are the winners of Nobel Prize 2016 for chemistry. They won noble prize for synthesis & design of Molecular machines.
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156.A change in which no new substances are formed is called _____________. (A) Physical Change (B) Chemical Change (C) Rusting (D) Galvanisation
(A) (SSC CGL 2017) Exp: Physical changes are changes in which no new product is formed. They are reversible in nature. These type of changes includes change in shape or state. eg:- Melting of ice, boiling of water etc.
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157.A change in which a substance undergoes a change in its physical properties is called _____________. (A) Chemical properties (B) Physical properties (C) Chemical change (D) Physical change
(D) (SSC CGL 2017) Exp: Physical changes are changes in which physical properties of substance change. These are reversible in nature. No new product is formed. eg:- Melting of Ice, boiling of water etc.
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159 The passage of an electric current through a conducting liquid causes ___________. (A) Galvanisation (B) Evaporation (C) Physical reaction (D) Chemical reaction
(D) (SSC CGL 2017) Exp: The passage of an electric current through a conducting liquid causes chemical reaction.
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160.A change in which one or more new substances are formed is called _________. (A) Physical change (B) Chemical change (C) Rusting (D) Galvanisation
(B) (SSC CGL 2017) Exp: A change in which one or new substances are formed is called as Chemical change. It is irreversible in nature as the product can not be converted into its base matter. Eg: digestion of food, burning of fuel etc.
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161.What is formed when Carbon dioxide is passed through lime water? (A) Copper sulphate (B) Calcium carbonate (C) Magnesium oxide (D) Baking soda
(B) (SSC CGL 2017) Exp: When carbon dioxide is passed through lime water, then solution becomes milky and a water insoluble substance calcium carbonate (CaCO3) is formed. Ca(OH)2 + CO2 CaCO3 + H2O If excess of CO2 is passed. then milkiness disappears due to formation of calcium bicarbonate.[Ca(HCO3) 2] which is water soluble.
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162.The temperature at which a solid melts to become a liquid at the atmospheric pressure is called its ___________. (A) Crystallisation (B) Melting point (C) Evaporation (D) Galvanisation
(B) (SSC CGL 2017) Exp: The temperature at which a solid melts to become a liquid at the atmospheric pressure is called its Melting point.
273
163.The melting point of ice is ____ K. (A) 253.16 (B) 263.16 (C) 273.16 (D) 283.16
(C) (SSC CGL 2017) Exp: Melting point is the temperature at which solid state melts to become liquid at the atmospheric pressure. The melting point of ice is 0°C or 273.16K.
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164. The substances which have very low ignition temperature and can easily catch fire with a flame are called _____________ substances. (A) Hazardous (B) Perilous (C) Incombustible (D) Inflammable
(D) (SSC CGL 2017) Exp: The substances which have very low ignition temperature & can easily catch fire with a flame are called as Inflammable substances. Eg: Oil, kerosene, petrol etc.
