Envi Engg Flashcards by Jose Gabriel H. Escorial

Suspended solid present in the waste water generated in blast furnace gas cooling and cleaning plant is removed by

A. biological oxygen pond.
B. radial settling tank (thickener) using coagulant (lime & ferrous sulphate).
C. lagoons.
D. filtration.

radial settling tank (thickener) using coagulant (lime & ferrous sulphate).

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Persons working in cement plants and limestone quarries are more prone to disease like

cancer
asthma
silicosis
flourosis (bone disease)

silicosis

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Particulates (< 1μm size) remaining suspended in air indefinitely and transported by wind currents are called

fumes
mists
smoke
aerosols

aerosols

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Operating principle of cyclone separator is based on the action of __________ dust particles.

diffusion of
centrifugal force on
gravitational force on
electrostatic force on

centrifugal force on

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Exposure to small amount of __________ results in high blood pressure & heart disease in human beings.

cadmium

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Maximum allowable concentration of CO2 in air for safe working is __________ ppm (parts per million).

50
1000
2000
5000

5000

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Tolerable limit of nitrogen oxides in air is __________ ppm.

0.1
1
5
25

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Iron & manganese present as pollutant in water can not be removed by

ion exchange process.
oxidation followed by settling & filtration.
lime soda process or manganese zeolite process.
chlorination.

chlorination

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In water chemical treatment plant, use of chloramines ensures

disinfection.
taste & odour control.
weed control in reservoirs.
removal of permanent hardness.

disinfection

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Which of the following is the common pollutant emitted from metallurgical smelters, thermal power plant and cement plants ?

NOx
Hg
SO2
F

SO2

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During which of the following operating conditions of an automobile, carbon monoxide content in the exhaust gas is maximum ?

Idle running
Acceleration
Cruising
Deaccelaration

Idle running

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H2S present in gaseous stream can be removed by adsorption on

silica gel
active carbon
bog iron
limestone powder

bog iron

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Inhalation of lead compounds present in automobile exhaust (using leaded petrol) causes

blood poisoning.
anaemia.
nervous system disorder.
all (a), (b) & (c).

all (a), (b) & (c).

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Replenishment of dissolved oxygen in water stream polluted with industrial waste occurs by

natural aeration of water stream.
photosynthetic action of algae.
both (a) & (b).
neither (a) nor (b).

both (a) & (b).

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Aerodynamic noise resulting from turbulent gas flow is the most prevalent source of valve noise in fluid ilow control. It is caused due to

Reynold stresses
shear forces
both (a) & (b)
neither (a) nor (b)

both (a) & (b)

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Smoke is produced due to

insufficient supply of combustion air and insufficient time for combustion.
poor quality of fuel and improper mixing of fuel & combustion air.
poor design & overloading of furnace.
all (a), (b) and (c).

all (a), (b) and (c).

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Fluorosis (a bone disease) is caused by the presence of high concentration of __________ in atmospheric air.

hydrocarbons
hydrogen flouride
hydrogen sulphides
nitrogen dioxide

hydrogen flouride

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Threshold Limit Value (TLV) is the maximum allowable concentration (i.e. safe limit) of pollutants in air. Safe limit for SO2 in air is __________ ppm.

5
500
1000
2000

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Main pollutants released from iron & steel industry is

CO, CO2 & SO2.
H2S, NO & SO3.
CO2, H2S & NO2.
SO3, NO2 & CO2.

CO, CO2 & SO2.

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Exposure to chemicals having carcinogenic properties cause

dermatitis (skin disorder)
cancer
asphyxiation (suffocation)
asthma

cancer

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Scale formation in boiler is controlled by

preheating of feed water.
reduction in hardness, silica & alumina in feed water.
keeping the pH value of feed water just below 7.
eliminating H2S in feed water.

reduction in hardness, silica & alumina in feed water.

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Noise level heard at a distance of about 100 metres from a jet engine with after burner is about __________ decibels.

120
140
170
200

170

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TLV of mercury in potable (drinking) water is about __________ ppm.

0.001
0.1
1
5

0.001

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Which is the best and the most effective method for the removal of organic contaminant present in the polluted water in very small quantity (say < 200 mg/litre)?

Lagooning
Activated carbon adsorption
Biological oxidation pond
Chemical coagulation

Activated carbon adsorption

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Which is a secondary air pollutant? Photochemical smog Sulphur dioxide Nitrogen dioxide Dust particles

Photochemical smog

Which of the following is the most detrimental for water used in high pressure boiler ? Silica Turbidity Phenol Dissolved oxygen

Silica

Turbidity of water is an indication of the presence of suspended inorganic matter dissolved solids floating solids dissolved gases

suspended inorganic matter

Presence of excess flourine in water causes dental cavity tooth decay fluorosis respiratory disease

fluorosis

Siderosis is a disease caused by the inhalation of __________ dust. coal silica iron none of these

iron

Which of the following pollutants is not emitted during volcanic eruptions ? SO2 H2S CO hydrocarbons

hydrocarbons

The main pollutant in waste water discharged from a petroleum refinery is oil (both in free and emulsified form). Free oil is removed by biological oxygen pond. aerated lagoons. trickling filters. gravity separator having oil skimming devices.

gravity separator having oil skimming devices.

Phenolic water generated in coke ovens & by-product plant attached to an integrated steel plant containing phenol in concentration of less than 100 mg/litre can be removed by chlorination treating in biological oxygen pond chemical coagulation none of these

treating in biological oxygen pond

Which of the following dust collection equipments is the least efficient (for sub-micronic particles) ? Dust catcher (gravity type) Cyclone separator Bag filter Hollow wet scrubber

Dust catcher (gravity type)

Bag filter design is predominantly dependent on gas temperature, as it affects the gas density & viscosity and the selection of filtering material. The pressure drop in a bag filter is inversely proportional to viscosity of gas. proportional to the viscosity & density of the gas. proportional to the pressure of the gas. both (b) and (c).

both (b) and (c).

Dust collection efficiency of a cyclone separator depends upon its diameter. inlet gas velocity. overall height. all (a), (b) & (c).

all (a), (b) & (c).

Ionisation potential employed in the industrial electrostatic precipitator is of the order of 30 to 70 kV DC 30 to 70 kV AC 230 V AC 230 V DC

30 to 70 kV DC

The widest explosive limit is of __________ , thereby making it the most explosive gas. acetylene petrol vapor hydrogen carbon monoxide

acetylene

Aerobic biological oxidation ponds used for the purification of polluted water destroys/removes pathogen from the sewage. is not very effective for nonbiodegradable substances (e.g. ABS) containing effluents. destroys/removes pathogen much more effectively if the sewage is chlorinated. all (a), (b) & (c).

all (a), (b) & (c).

Polluted water having low BOD are most economically treated in sedimentation tanks oxidation ponds sludge digester clarifier

oxidation ponds

Tri-sodium phosphate is used in boiler water treatment to reduce turbidity caustic embrittlement suspended silica dissolved oxygen

caustic embrittlement

The commonest form of iron & manganese found in ground water as pollutant is in the form of their carbonates bi-carbonates chlorides sulphides

bi-carbonates

80% less than 200 mesh size particles are called smoke powder grit aggregates

powder

Coal washing waste water containing about 3% suspended solids (comprising of clay, slate, stone etc.) is treated for solid particles removal by chemical coagulation. in sedimentation tanks equipped with mechanical scrapper. in vacuum filter. in clarifiers.

in sedimentation tanks equipped with mechanical scrapper.

Inhalation of lead compounds present in the automobile exhausts (using leaded petrol) causes blood poisoning. anaemia. nervous system disorder. all (a), (b) and (c).

all (a), (b) and (c).

TLV of ozone (O3) and phosgene (COCl2) in air is __________ ppm. 0.1 25 100 1000

0.1

Most of the atmospheric air pollutants are present in large quantity in stratosphere thermosphere trophosphere mesosphere

trophosphere

Pick out the wrong statement. Caustic embrittlement of boiler's metallic parts is caused by high concentration of caustic soda in boiler feed water. Cooling and freezing of water kills the bacteria present in it. With increasing boiler operating pressure of steam, the maximum allowable concentration of silica in feed water goes on decreasing. Dissolved oxygen content in high pressure boiler feed water should be nil.

Cooling and freezing of water kills the bacteria present in it.

'Pneumoconiosis' is a disease caused by the inhalation of __________ dust. coal uranium ore iron ore lime

coal

The ratio of oxygen available to the oxygen required for stabilisation of sewage is called the bacterial stability factor. relative stability. biological oxygen demand (BOD). oxygen ion concentration.

relative stability.

Pick out the wrong statement. The concentric atmosphere layer just above troposphere is called stratosphere, which is rich in ozone. Mesosphere is characterised by very low atmospheric pressure and low temperature. Troposhere is a dusty zone containing water vapor and clouds. The radio waves used in the long distance radio communication are reflected back to earth by stratosphere.

The radio waves used in the long distance radio communication are reflected back to earth by stratosphere.

Most efficient and suitable dust removal equipment for removal of flyash from flue gas in a thermal power plant is the gravity settling chamber cyclone separator electrostatic precipitator bag filter

electrostatic precipitator

Which of the following is not a secondary air pollutant ? Ozone Photochemical smog Sulphur dioxide All (a), (b) & (c)

Sulphur dioxide

The concentration of water vapour in troposphere, which depends upon the altitude & temperature varies in the range of zero to __________ percent. 1 4 8 12

The main industrial source of emission of hydrogen sulphide air pollutant is petroleum refineries. coal based thermal power plants. pulp and paper plant. metallurgical roasting & smelting plant.

coal based thermal power plants.

Waste/polluted water discharged from electroplating, blast furnace and coal mining industries contain mainly __________ substances. radioactive organic inorganic none of these

inorganic

Sound produced by an automobile horn heard at a distance of 1.5 metres corresponds to about __________ decibels. 90 120 150 180

120

Moist atmospheric air at high temperature (e.g., in summer) having high concentration of sulphur dioxide causes fading of dyes on textiles. corrosion, tarnishing & soiling of metals. reduced strength of textiles. all (a), (b) and (c).

all (a), (b) and (c).

Nitrogen oxides (NOx) is not produced in the __________ industry. nitric acid making nitrogenous fertiliser detergent any of these

detergent

World's worst radioactive pollution was caused by nuclear reactor disaster which occured in Arizona (U.S.A.) Chernobyl (undivided U.S.S.R.) Pensylvania (U.S.A.) Moscow (U.S.S.R.)

Chernobyl (undivided U.S.S.R.)

Dissolved oxygen content in river water is around __________ ppm. 5 100 250 500

Oil and grease present in an emulsified state in waste water discharged from industries can be removed by biological oxidation. skimming off. settling out using chemical reagents. chlorination.

settling out using chemical reagents.

The amount of chemical coagulant added for treatment of polluted water __________ with increase in temperature of the polluted water to be treated. decreases. increases. remains constant. may increase or decrease ; depends on the chemical characteristics of polluted water.

decreases

Particles having diameter greater than 75 μm (micrometer = 10-6 mm) are called grit dust powder smoke

grit

Which of the following is the most severe air pollutant ? hydrocarbons NOx SO2 CO

NOx

Presence of bacteria in potable (drinking) water causes turbidity disease bad odour bad taste & colour

disease

What are the methods of treatment & disposal of radioactive wastes ? Evaporation & chemical precipitation. Biological methods & adsorption in ion exchange materials. Fixing into a solid mass with cement and sinking deep in the sea. All (a), (b) & (c).

All (a), (b) & (c).

Bacterial aerobic oxidation of polluted water in biological oxidation ponds is done to purify it. Presence of bacteria helps in coagulation and flocculation of colloids. oxidation of carbonaceous matter to CO2. nitrification or oxidation of ammonia derived from breakdown of nitrogeneous organic matter to the nitrite and eventually to the nitrate. all (a), (b) and (c).

all (a), (b) and (c).

Main pollutant present in automobile exhaust is CO CO2 NO hydrocarbons

Maximum allowable noise exposure limits for a man working for 8 hours a day in a noisy chemical plant is about __________ decibels. 20 60 90 120

Industrial workers working in leather tanning & manufacturing units are prone to suffer from respirtory ailments (e.g. bronchitis). skin diseases (e.g. dermatities). silicosis. blurred vision.

skin diseases (e.g. dermatities).

Pick out the wrong statement. Biological oxygen demand (B.O.D.) value of a sewerage sample is always lower than its chemical oxygen demand (C.O.D.) value. Environmental pollution by NOx emission is much higher by four stroke petrol engines as compared to the two stroke engines. Temperature in stratosphere rises with increasing altitude. The characteristic of a green house body is that it allows the long wavelength incoming solar radiation to come in but does not allow the short wavelength infra red radiation to escape out of the earth's atmosphere.

Peroxyacyl nitrate (PAN), a pollutant is found in the automobile exhaust. flue gas of coal based power plant. exhaust of nitric acid plant. exhaust of sulphuric acid plant.

automobile exhaust.

Foaming and priming in boiler operation can be reduced by reduction in __________ in feed water. turbidity color (Hazen) total solids all (a), (b) & (c)

all (a), (b) & (c)

Ambient noise level can be reduced by __________ decibels by planting trees (like coconut, neem etc.) near public utility buildings (like hospitals & schools). 1-2 5-10 15-20 25-30

5-10

Pick out the wrong statement. Catalytic converter is fitted in automobiles to reduce carbon monoxide concentration in exhaust emissions. Inhalation of pollutant carbon monoxide results in death by asphyxiation. Sulphur dioxide is the main pollutant emitted from the exhaust of petrol driven automobiles. Decomposition of plants containing chlorophyll is a natural source of carbon monoxide in atmosphere.

Sulphur dioxide is the main pollutant emitted from the exhaust of petrol driven automobiles.

Which of the following radioactive wastes emits all α, β & γ rays and hence is the most hazardous of all radioactive emitters? I-131 Sr-90 Au-198 Ra-226

Ra-226

COD of raw municipal sewage may be in the range of about __________ mg/litre. 1-2 5-10 90-120 1500-2500

90-120

Maximum permissible turbidity in potable water is __________ ppm. 1 10 250 1000

Presence of __________ hardness is responsible for the temporary hardness in water. carbonate calcium choride sulphate

calcium

Dose of chlorine for disinfection of water is about __________ mg/litre of water. 0.01 0.1 0.3 1

A shallow pond in which the sewage is retained and biologically treated is called oxidation Imhoff tank lagoon skimming tank

oxidation

Which is the most practical and economical method for removal of suspended solid matter from polluted water ? Sedimentation Skimming off Chlorination Biological oxidation

Sedimentation

Atmospheric pollution caused by the exhaust gas of supresonic transport air-crafts is mostly in the atmospheric region called thermosphere stratosphere troposphere mesosphere

stratosphere

Iron & manganese present in the polluted water is removed by simple filtration. oxidation followed by settling & filtration. chemical coagulation. chlorination only.

oxidation followed by settling & filtration.

Water effluent generated in printing industry is decolourised by ion exchange technique. reverse osmosis. electrolytic decomposition. adsorption.

electrolytic decomposition.

Thermal pollution of water increases its toxicity and oxidation of oxygen demanding waste besides favouring bacterial growth. A rise in water temperature by 10°C, doubles the toxic effects of __________ present in it. coal ash potassium cyanide ortho-xylene none of these

potassium cyanide

__________ can not control the noise pollution. Use of silencers Green house gases Vibration damping Tree plantation

Green house gases

Ozone level is generally found to be depleted in India in the month of February July April December

December

Noise level during normal conversation among men is about __________ decibles. 10 45 90 115

'Particulate' air pollutants are finely divided solids and liquids. Which of the following is not a 'particulate' ? Dust & mists Smoke & fumes Photochemical smog & soot None of these

None of these

Foul odour and bad taste of water is removed by treating with alum bleaching powder activated carbon copper sulphate.

activated carbon

Presence of __________ in water stream are deleterious to aquatic life. soluble and toxic organics. suspended solids. heavy metals and cynides. all (a), (b) & (c).

all (a), (b) & (c).

Acute danger to human life (i.e. death) exists, if the concentration of CO2 in atmospheric air exceeds __________ percent (by volume). 1 3 7 20

Methyl iso-cynate (MIC) gas (TLV <1 ppm), which caused Bhopal gas tragedy in 1984 falls under the category of __________ toxic gas. moderately highly extremely very extremely

very extremely

Noise level heard inside a bus in busy city traffic or inside a sub-way train corresponds to about __________ decibels. 75 95 120 140

Presence of volatile compounds like gasoline, oil, alcohol, ether etc. in municipal sewers may cause explosion non biodegradable foam undesirable plant growth corrosion

explosion

Noise produced by cooling fans (employed in air cooled heat exchangers or cooling tower) is mainly caused due to the turbulence created by blade passage through air. It can be reduced by use of a slower fan with greater number of blades. of increased diameter. both (a) & (b). neither (a) nor (b).

both (a) & (b).

Presence of soluble organics in polluted water causes undesirable plants growth. depletion of oxygen. fire hazards. explosion hazards.

depletion of oxygen.

Which of the following pollutants, if present in atmosphere is detectable by its odour ? CO SO2 NO2 CO2

SO2

Exposure to chemicals having carcinogenic properties cause dermatitis (skin disorder) cancer asphyxiation asthma

cancer

In water treatment plant, zeolite process is used to remove the __________ of water. acidity alkalinity hardness iron & zinc

hardness

For existence of aquatic life in water, the dissolved oxygen content in it, should not be less than __________ ppm. 10000 5 500 1000

Fresh sewage is __________ in nature. acidic neutral alkaline highly acidic

alkaline

In a sedimentation tank, the detention period for water ranges from __________ hours. 2 to 4 8 to 12 16 to 20 24 to 32

2 to 4

On prolonged exposure to high concentration of carbon monoxide (> 5000 ppm), man dies because of clotting of blood. of jamming of respiratory tract. it forms carboxyhaemoglobin by combining with haemoglobin of blood, thereby making it incapable of absorbing oxygen. it forms CO2 by combining with oxygen present in the blood.

it forms carboxyhaemoglobin by combining with haemoglobin of blood, thereby making it incapable of absorbing oxygen.

Workers working in __________ industry are most prone to white lung cancer. coal mining limestone mining textile asbestos

textile

A standard test for determination of hardness in water is termed as __________ test. EDTA electometric total count presumptive

EDTA

TLV of lead for public sewer/waste water is about __________ ppm. 1 25 150 650

Presence of nitrates in water in excess of 50 ppm causes mathenoglobenemia gastroentetitis asphyxiation tooth decay

mathenoglobenemia

In sewage treatment, the detention period allowed for oxidation ponds ranges from __________ weeks. 1 to 2 4 to 5 9 to 10 15 to 20

4 to 5

Coal mines drainage waste water (acidic in nature) results from the earth's water percolating through the voids created in coal bed during mining. This polluted water which either drains out naturally to water courses or are removed before starting the mining is neutralised by alkali treatment. left as such without any treatment. diluted with fresh water to reduce its acidity. none of these.

neutralised by alkali treatment.

Fine grit present in sewage is removed in the __________ during sewage treatment. grit chamber detritus tank trickling filter skimming tank.

detritus tank

The lowest layer of atmosphere is known as the stratosphere troposphere ionosphere none of these

troposphere

As per the world health organisation (WHO) specification, the maximum permissible concentration (i.e., TLV) of particulate matter in air is __________ μg/m3.(μg-microgram) 10 90 800 750

Which of the following is not a weightless pollutant ? SPM Thermal pollution Radioactive rays Noise pollution

SPM

Global warming may result in flood cyclone decrease in food productivity all (a), (b) and (c)

all (a), (b) and (c)

Which of the following is the most lethal water pollutant ? Phenol and cynide Chlorine Alkalis Suspended solids

Phenol and cynide

Presence of carbon monoxide in atmosphere produced by decomposition of chlorophyl and haemoglobin breakdown of some animals, beyond TLV (>50 ppm) acts as a green house gas thereby raising earth's temperature. causes asphyxia. causes increase in sea level. inhances the green house effect.

causes asphyxia.

The earth's atmosphere is an envelope of gases present upto a height of about __________ kms. 10 200 1000 2000

200

Which of the following is an adsorbant used for the removal of SO2 from gas/air ? Bog iron Limestone powder or alkalised alumina Silica gel Active carbon

Limestone powder or alkalised alumina

Higher concentration of nitrogen dioxide in atmospheric air causes cancer bronchitis asphyxiation corrosion

bronchitis

Ozone is a primary pollutant. a secondary pollutant. impervious to ultra-violet rays. both (b) and (c)

both (b) and (c)

The permissible color for domestic water supply is __________ ppm. 1 20 100 1000

High noise levels produced during operation of fans and compressors can be reduced by using mufflers (silencers). accoustical absorbent. lagging of noisy duct. none of these.

mufflers (silencers).

The Killer gas which caused Bhopal gas tragedy in 1984 was phosgene methyl iso-cynate (MIC) carbon monoxide sulphur dioxide

methyl iso-cynate (MIC)

Aerosols present in atmospheric air may be positively charged. negatively charged. neutral. combination of all (a), (b) & (c).

combination of all (a), (b) & (c).

Ethanolamine is an absorbant used for the removal of __________ from air/gas. HF SO2 H2S both (b) & (c)

both (b) & (c)

Which of the following causes death by asphyxiation, if its presence in atmospheric air exceeds maximum allowable concentration (i.e. > 50 ppm) ? Benzopyrene Peroxyacyl nitrate Carbon monoxide Sulphur dioxide

Carbon monoxide

__________ plant emits large amount of SO2 as an air pollutant. Nitric acid Sulphuric acid Chloralkali Iron & steel

Sulphuric acid

Noise pollution level in a chemical plant is expressed in roentgen decibel hertz none of these

decibel

The maximum permissible noise level to which a man working in a chemical plant can be exposed for eight hours per day is about __________ decibels. 60 90 105 120

The most commonly used chemical coagulant in water treatment is ferrous sulphate alum lime hydrazine

alum

The biological decomposition of organic substances in wastes controlled conditions is called incineration biological oxidation composting none of these

composting

Lung cancer & DNA breakage are the major ill effects of excessive ozone exposure to human beings. Ozone layer depletion in the atmosphere is mainly caused by the presence of CO2 SO2 hydrocarbons CFC (chloro fluoro carbon)

CFC (chloro fluoro carbon)

Smog is not formed due to the presence of __________ in the atmosphere. SO2 NOx CO2 any of these

CO2

Pick out the correct statement. Deforestation helps in controlling the green house effect. Global warming is detrimental for increase in food productivity and may cause flood and cyclone. Lightening discharges are natural source of production of SO2 & H2S pollutant. Sulhur dioxide causes death by asphyxiation.

Global warming is detrimental for increase in food productivity and may cause flood and cyclone.

Which of the following is not a source of ozone emission in the atmosphere ? Refrigerators. Xerox machines. Dermatological photo-therapy equipments. High voltage electrical equipments.

Refrigerators

Oceans act as sinks for atmospheric gases including carbon dioxide whose concentration in the atmosphere is increased by the forestation rain green house effect vegetation

green house effect

Pick out the correct statement. Chemical oxygen demand (COD) is a measure of chemically oxidisable organic matter present in water. COD is determined by oxidising the organic matter present in water with potassium dichromate in cone, sulphuric acid solution at boiling temperature for specified time. COD is related to BOD of a given waste in water but the relationship varies for different wastes. Typically COD of potable water may be 1-2 mg/litre. all (a), (b) and (c).

all (a), (b) and (c).

The upper layer of atmosphere is called the stratosphere troposphere ionosphere none of these

stratosphere

Which of the following is the most widely used disinfectant in water treatment ? Chlorine Irradiation of water by ultraviolet light Cation exchanger Coagulation

Chlorine

Pick out the wrong statement Low ozone layer thickness in polar regions is due to cold climatic conditions Amount of unburnt hydrocarbons emitted by two stroke petrol engine is more as compared to that emitted by a four stroke engine. Carbon monoxide present in the two stroke petrol engine exhaust is much less as compared to that emitted from a four stroke engine. Mercury as a pollutant can enter the blood stream & the digestive system/ lungs and is responsible for causing minamate disease.

Carbon monoxide present in the two stroke petrol engine exhaust is much less as compared to that emitted from a four stroke engine.

Phenolic water generated in coke ovens & by-product plant of a steel plant are disposed off by quenching of hot coke. discharging in the river stream. filtration and recycling for cooling coke oven gas. none of these.

quenching of hot coke.

5-200 μm size particles are called colloids or aerosols powder dust smoke

colloids or aerosols

The progressive warming up of the earth's surface is mainly due to the automobile exhaust. blanketing effect of CO2 in the atmosphere. de-forestation. thickening of ozone layer.

blanketing effect of CO2 in the atmosphere.

The effect of increase in carbon dioxide level of the atmosphere and its profound effect on our climate is called the catalytic conversion green house effect global warming both (b) and (c)

both (b) and (c)

Arsenic pollutant is not generated in____industries. tanneries glass & ceramic beverages any of these.

beverages

The resistance of water to the passage of light through it is a measure of the turbidity color hardness dissolved gases

turbidity

Color test of water is done with an instrument called tintometer colorimeter electro-chemical cell turbidimeter

tintometer

Which of the following gases is having the widest explosion limit (about 2 to 81% gas in gas-air mixture), rendering it the property of the most explosive gas ? Hydrogen Acetylene Carbon monoxide Ammonia

Acetylene

Pick out the wrong statement pertaining to 'green house' for the plants. 'Green house' (made of glass) allows visible sunlight (i.e., short wavelength solar radiation like ultra-violet rays) to pass through the glass and heat up the soil thereby warming up plants inside it. The emitted longer wavelength radiation (e.g., infrared) is partly reflected and partly absorbed by the glass of the green house. 'Green house effect' in earth's atmosphere is due to increasing CO2 level in atmosphere. where CO2 acts like the glass of 'green house' thereby warming up the earth's surface. 'Green house' is colder than the outside atmosphere.

'Green house' is colder than the outside atmosphere.

In water treatment, alum[Al2(SO4)3] is used for the process of filtration coagulation sedimentation disinfection

coagulation

Pick out the one which is not a chemical coagulant. Aluminium sulphate Ferrous sulphate Hydrated lime Chloramine

Chloramine

Presence of iron and manganese in water causes reduction in its dissolved oxygen content. discoloration of bathroom fixtures. temporary hardness. none of these.

discoloration of bathroom fixtures.

Septic tanks are used for the __________ of the deposited solids. separation anaerobic decomposition aerobic decomposition none of these

anaerobic decomposition

Death may occur, when SO2 concentration in atmospheric air exceeds __________ ppm. 20 100 400 200

400

Which of the following acts as a natural source of air pollution ? Forest fire Deforestation Volcanic eruption None of these

Volcanic eruption

Higher concentration of CO2 in atmosphere allows visible solar radiation (ultraviolet) of short wave-length to pass through. reflects and absorbs the longer wavelength (infra-red) radiations. prevents solar heat being radiated out completely, resulting in 'heat trap' i.e., global warming. all (a), (b) and (c).

all (a), (b) and (c).

Permissible safe limit (TLV) of __________ toxic gas is 100-1000 parts per million (ppm). highly moderately extremely very extremely

moderately

Radioactive substances present in the polluted water stream can be removed by biological oxygen treatment. coagulation and filtration. adsorption in ion exchange materials. none of these.

adsorption in ion exchange materials.

In the context of the chemical process industries, the term BOD is normally associated with the characterisation of solid wastes. organic concentration in gaseous effluents. characterisation of liquid effluents. characterization of boiler feed water.

characterisation of liquid effluents.

Noise emitted by a ventilation fan at a distance of 3 metres is about __________ decibels. 85 105 125 145

105

Inhalation of silica dust causes a disease called bronchitis silicosis pneumoconiosis none of these

silicosis

Solid content in most of the domestic sewage is about __________ percent. 0.001 0.1 5 10

0.1

In troposphere (the weather domain), the temperature 't' at height 'h' above the spa level in metres is given by (where, temperature at sea level is 15°C and t is in °C.) t = 15 - 0.0065h t = 15 + 0.0065h t = 0.0035h -15 t = 15 - 0.0035h

t = 15 - 0.0065h

High noise level in a chemical plant can be controlled by the suppression of noise at the source itself. path control of noise. protection of operating personnel. all (a), (b) & (c).

all (a), (b) & (c).

Limestone powder is injected during pulverised coal burning in boilers to __________ the flue gases. reduce SO2 content in catalytically convert SO2 to SO3 in increase the dew point of none of these.

reduce SO2 content in

Main pollutants released from petroleum refineries is CO, SO2 & H2S. CO2, NO & SO3. CO2, H2S & NO2. SO3, NO2 & CO2.

CO, SO2 & H2S.

Maximum permissible limit of industrial noise as recommended by World Health Organisation (WHO) is __________ decibels. 35 75 95 105

Which of the following is a green house gas other than CO2 ? Methane Nitrous oxide Chlorofluro carbons (CFC) All (a), (b) and (c)

All (a), (b) and (c)

Automobile exhaust is passed through two compartments catalytic converter employing platinum as catalyst for conversion of CO into CO2 in the second compartment. conversion of NOx into N2 and NH3 in the first compartment. oxidation of unburnt hydrocarbon fuel in the second compartment. all (a), (b) and (c).

all (a), (b) and (c).

Lagooning process is mainly a means of the sludge disposal. reduction of excessive flow in sewers. biological treatment of wastes. none of these.

sludge disposal.

Carbon monoxide is a pollutant, which causes respiratory disease (e.g. asthma). asphyxiation (suffocation) leading to death. retardation in crop growth. damage to building materials like marble.

asphyxiation (suffocation) leading to death.

Pollution by particulate matter emission in the atmosphere does not take place during metal grinding machining cutting polishing

polishing

Direct reaction of unsaturated hydrocarbons with either NO or NO2 produces an eye irritating pollutant compound known as photochemical smog. peroxy acetyl nitrate (PAN) or methyl nitrile. benzopyrene. poly acrylonitrile

peroxy acetyl nitrate (PAN) or methyl nitrile.

Pick out the correct statement. Noise from ball mills can be dealt with by fibre glass lined enclosures. Noise from vibrating chutes can be reduced by lining the metallic chute with rubber. Noise of conveyor belt system is reduced by using urethane coated cloth conveyor belts and rubber/plastic covered metallic rollers. all (a), (b) & (c).

all (a), (b) & (c).

BOD of raw municipal sewage may be in the range of about __________ mg/litre. 1-2 5-10 150-300 2000-3000

150-300

Irradiation of water by ultraviolet light of suitable wavelength is commonly used for disinfection of water in food industry. municipal sewage treatment. petroleum refinery. iron & steel plant.

food industry.

When the concentration of SO2 in air is greater than __________ ppm, it gives a pungent smell. 0.01 0.1 1 4

Presence of a certain minimum quantity of flourine is desirable in potable water to prevent dental cavities scale formation water-borne disease corrosion

dental cavities

Pick out the wrong statement. Benzopyrene which causes cancer is present in traces in tobacco, charcoal & petrol driven automobile exhaust. NO2 is capable of penetrating the troposphere and can absorb both ultraviolet & visible light. Hydrocarbon pollutants are produced by sweet gum, oak & natural rubber trees. H2S is not at all produced during combustion of sulphur bearing fuels as all the sulphur is oxidised to SO2.

H2S is not at all produced during combustion of sulphur bearing fuels as all the sulphur is oxidised to SO2.

Which of the following is not an air pollutant ? Ozone Carcinogens Pesticides Metallic powders

Ozone

Presence of high concentration of ozone and smog in atmospheric air causes the embrittlement & decrease of folding resistance of paper. cracking of rubber products. fading of dye on textiles. damage of electrical insulator on high tension power line.

cracking of rubber products.

Algae growth in water is controlled by deoxidation chlorination bleaching aeration

chlorination

__________ is removed from water by lime-soda process. Foul smell and taste Iron and manganese Temporary hardness Permanent hardness

Temporary hardness

Most of the bacteria in sewage are parasitic saprophytic anerobic none of these

saprophytic

Which of the following is the most major constituents of air pollutants ? Oxides of sulphur Oxides of nitrogen Carbon monoxide Hydrogen sulphide

Oxides of sulphur

Shouting by a man at his full voice corresponds to a voice level of about __________ decibels. 25 50 80 120

Carbonaceous particles having size less than 1 μm are called grit aggregates aerosols smoke

smoke

__________ substances present in sewage are removed in grit chamber during sewage treatment. Organic Fatty Inorganic Dissolved

Inorganic

The type of bacteria which is active in trickling filter during biological treatment of sewage is the __________ bacteria. anaerobic saphrophytic aerobic parasitic

aerobic

Presence of dissolved impurities of __________ is responsible for the red brownish color of water. carbonates bi-carbonates iron & manganese arsenic

iron & manganese

TLV of aldrin in public water supply system is about __________ μg/litre. 0.5 17 357 1097

A gas is termed as non-toxic, if its maximum permissible concentration (TLV) ranges from __________ ppm. 1000 to 2000 3000 to 6000 6000 to 9000 10000 to 100000

10000 to 100000

Removal of __________ is accomplished by aeration of water. dissolved gases suspended solids dissolved solids none of these

dissolved gases

Green house effect is accentuated by deforestation. rapid industrialisation. increased transportation activity. all (a), (b) and (c).

all (a), (b) and (c).

Thermal pollution due to excessive heat & temperature in the working place causes reduction in working efficiency of manpower. fatigue. high breathing rate. all (a), (b) & (c).

all (a), (b) & (c).

High concentration of carcinogenic hydrocarbon pollutants in atmospheric air causes cancer silicosis respiratory disease (e.g., asthma) reduced crop yield

cancer

World environment day is observed every year on the 5th of June December July September

June

The major reason of hydrodynamic noise (i.e., noise resulting from liquid flow) is pipe vibrations. cavitation. boundary layer separation. fluctuation in liquid flow.

cavitation

The term Biological Oxygen Demand (BOD) is used in relation to potable water cooling water distilled water industrial effluents

industrial effluents

The destruction of water-borne pathogens is termed as disinfection of water. Which of the following is a water disinfectant ? Chlorine Alkalis Benzene hexachloride Alkyl benzene sulphonate (ABS)

Chlorine

Disinfection of water is done to destroy pathogenic bacteria and thus prevent water-borne diseases. Disinfection of water may be done by the use of ozone and iodine. chlorine or its compounds. ultraviolet light for irradiation of water. all (a), (b) & (c).

all (a), (b) & (c).

Which of the following processes is involved in the biochemical treatment of sewage effluents ? Oxidation Reduction Dehydration Fermentation

Oxidation

Infective bacteria in water is killed by the __________ process. sterilisation aeration disinfection none of these

sterilisation

Fluorosis is caused due to the presence of excessive amount of __________ in drinking water. mercury lead fluoride arsenic

fluoride

Presence of nitrogen and phosphorous in waste water discharged into lakes and ponds causes foaming odour nuisances undesirable plant growth turbidity

undesirable plant growth

Pick out the wrong statement. Biological oxygen demand (BOD) is a characteristic and not a constituent of water. BOD is a measure of the amount of oxygen which will be demanded & used in 5 days by the biological decomposition of the organic matter present in water stream present as food for the living organism. BOD is expressed in mg/litre (typically, BOD=2.5 mg/litre for potable water). none of these

none of these

The pH value of potable water should be between 1 to 1.5 6.5 to 8 13 to 14 4 to 5

6.5 to 8

Maximum permissible limit of mercury in human blood is __________ micrograms/100 c.c. 1 7 19 82

Which of the following pollutants is absent in the emissions from a fertiliser plant ? SO2 & SO3 NO2 NH3 CO

Salt content in sea water is about __________ percent. 0.5 1 3.5 10

3.5

Noise level inside a jet air liner in normal flight is about __________ decibels. 80 100 125 145

100

What is the major constituents of waste/polluted water discharged from textile, pulp & paper, tanning, distillary, dairy and meat packing industries ? Radioactive substances Natural organic products Inorganic pollutants None of these

Natural organic products

Water filtration rate in a rapid sand filter ranges from __________ kilolitres/m2/hr. 0.1 to 1 3 to 6 10 to 15 15 to 20

3 to 6

Hazardous/polluting chemical industries should have an 'exclusion zone' with a green belt and general public access prohibited around it, covering a radius of ____ metres. 100 1000 400 4000

1000

Maximum permissible residual chlorine in treated water should be __________ mg/litre. 0.001 to 0.01 02 to 0.3 2 to 3 5 to 10

02 to 0.3

Which of the following is the most active zone of atmosphere in which weathering events like rain, storm & lightning occur ? Thermosphere Troposphere Stratosphere none of these

Troposphere

Which is the most widely used coagulant for the treatment of turbid water ? Alum (aluminium sulphate) Lime Ferric chloride Sodium aluminate

Alum (aluminium sulphate)

Which of the following is not a natural source of air pollution ? Volcanic eruptions and lightening discharges. Biological decay of vegetable matter. Photochemical oxidation of organic matter. None of these.

None of these.

Threshold limit value (TLV) i.e., the maximum permissible safe limit of phosgene gas which Hitler used to use to kill his enemies in 'gas chamber' is about __________ ppm. <1 10-100 100-200 100-1000

Photochemical smog is formed from automobile exhaust by reaction of hydrocarbon & nitric oxide in presence of sunlight. appears only on sunny days. is harmful for crops and trees also besides causing eye irritation & asthma. all (a), (b) & (c)

all (a), (b) & (c)

Reinglemann chart is used for the measurement of the combustibles present in automobile exhaust. smoke density from a chimey. exhaust gas density. flue gas temperature.

smoke density from a chimey.

Disinfection of water is done to remove color bad taste foul odour bacteria

bacteria

Which of the following fine dust removal equipments is the most efficient ? Bag filter Scrubber Electrostatic precipitator Cyclone separator

Electrostatic precipitator

Which of the following industries discharge mercury as a pollutant ? Chloro-alkali industry Tanneries Beverage plant Phosphoric acid plant

Chloro-alkali industry

Threshold limit value (TLV) of CO in air is __________ ppm. 5 50 2000 5000

Lead exhausted in the atmosphere by automobiles using leaded petrol (i.e. tetraethyl lead for improving octane number) is a lethal air pollutant which causes paralysis of muscles & loss of appetite. nervous depression. gastritis & diarrhea. all (a), (b) and (c).

all (a), (b) and (c).

Oilish impurities present the effluent discharged from the electroplating industry is normally not removed by chemical coagulation floatation & skimming centrifugation ultrafiltration

chemical coagulation

In large thermal power stations very fine particulates present in flue gas are removed by wet scrubber bag filter electrostatic precipitators dust catcher

electrostatic precipitators

Threshold limit value (TLV) means maximum permissible/acceptable concentration. TLV of phosgene in air is about __________ ppm (parts per million). 0.002 0.2 1.2 4.8

0.2

The density of the gases (present in air) decreases with increasing altitude to such an extent, that about 70% of the mass of atmospheric air is found in the lower 5 km. of the atmosphere. This lower region of atmosphere is called the ionosphere troposphere stratosphere none of these

troposphere

Biological oxidation ponds remove organic matters present in the polluted water by using the activities of bacteria and other micro organisms. aerobic oxidation. both (a) & (b). neither (a) nor (b).

both (a) & (b).

Which of the following is an adsorbant for removal of nitrogen oxides from gas/air ? Active carbon Silica gel Bog iron (iron oxide) Pulverised limestone

Silica gel

Out of the following, TLV of __________ is the minimum (about 0.02 ppm). phosgene bromine MIC (methyl iso-cynate) ozone

MIC (methyl iso-cynate)

The average thickness of ozone layer in stratosphere is about __________ dobson unit (DU). 20 230 750 1500

230

Polyvinyl chloride containers are not suitable for storing foodstuffs woolen clothes metallic powder none of these

foodstuffs

Presence of nitrogen in high concentration in contaminated air reduces partial pressure of oxygen in lungs, thereby causing asphyxia (suffocation) leading to death from oxygen deficiency. Concentration of N2 in contaminated air at which it acts as a natural asphyxant is ≥ __________ percent. 84 88 80 92

TLV of ammonia, nitrogen dioxide and phenol vapor in air is __________ ppm. 5 100 1000 2000

Corrosion in boilers can be prevented by deaeration of feed water. enhancing pH of feed water by adding alkali. feeding sodium sulphite or hydrazine phosphate to the boilers, which combines with oxygen and prevents corrosion. all (a), (b) and (c).

all (a), (b) and (c).

Water filtration rate in a slow sand filter ranges from __________ litres/m2/hr. 10 to 20 100 to 200 1500 to 2500 4000 to 5000

100 to 200

Lagoons used for purification of polluted water are large shallow artificial lakes also known as clarification lakes, maturation ponds or oxidation ponds. use micro-organisms/bacteria in presence of dissolved oxygen. gives an excellent final effluent (with 3 to 4 lagoons arranged in series) having suspended solid < 1 mg/litre and BOD = 3.8 mg/litre. all (a), (b) & (c).

all (a), (b) & (c).

The principal gas evolved from sludge digestion tank is CO CO2 CH4 N2

CH4

There are thirteen metals which are treated as pollutants. Which of the following metals is not a pollutant ? Mercury Arsenic Aluminium Lead

Aluminium

The function of skimming tank in sewage treatment is to remove __________ substances. dissolved solid suspended solid oil & fatty gritty & inorganic

oil & fatty

The weakest sound that can be heard by a person in a quiet environment is equivalent to __________ decibel. 1 5 10 20

Inorganic impurities causing water pollution is fats carbohydrates salts of metals protein

salts of metals

The main type of sludge gas evolved during sewage treatment in Imhoff tank is CO2 CH4 CO H2

CH4

From pollution control point of view, the maximum permissible concentration of sulphur dioxide in atmospheric air is about __________ ppm. 1 5 50 500

The pH value of oxidised sewage is about 1.8 6.2 7.3 13.4

7.3

Smog is nothing but black smoke. a combination of smoke and fog. a liquid particle resulting from vapor condensation. a solid particle e.g. flyash.

a combination of smoke and fog.

_________ is the process of killing organism in water. Coagulation Sterilisation Disinfection Sedimentation

Disinfection

Reingleman chart No. 2 corresponds to __________ percent black smoke. 10 20 40 80

Which of the following is a manmade source of air pollution ? Automobile exhaust. Forest fire. Bacterial action in soil and swamp areas All (a), (b) and (c).

Automobile exhaust

Which is the most efficient dust removal equipment for removal of sub-micronic dust particles from blast furnace gas ? Packed scrubber Gravity settling chamber Electrostatic precipitator Hydrocyclone

Electrostatic precipitator

Insufficient washing of sand grains in a rapid sand filter causes air binding shrinkage of filtering media mud balls expansion of filtering media

mud balls

Which of the following sources is responsible for maximum air pollution ? Industrial chimney exhaust. Forest fire. Automobiles exhaust. Photochemical oxidation of organic matter.

Automobiles exhaust.

Which of the following is the most efficient for removal of very finely divided suspended solids and colloidal matter from the polluted water stream ? Sedimentation tank Circular clarifier Mechanical flocculation Chemical coagulation

Chemical coagulation

In sewage treatment, its sedimentation is speeded up by commonly adding hydrochloric acid. lime. copper sulphate. sodium sulphate.

lime.

Noise level in a quiet private business office is about __________ decibels. 25 50 70 85

'Safe limit' called Threshold Limit Value (TLV) of carbon monoxide in atmospheric air is < 50 ppm. The main source of carbon monoxide pollutant in air is the industrial chimney exhaust. automobiles exhaust. photochemical reaction in polluted atmosphere. burning of domestic fuel.

automobiles exhaust.

Inhalation of silica dust by human being causes asphyxiation shortness of breath tuberculosis both(b) & (c)

both(b) & (c)

Which of the following air pollutants is not toxic to vegetation i.e., doesn't cause vegetation damage ? Smog & ozone Hydrogen fluoride & nitrogen oxides Sulphur dioxide & spray of weed killers Carbon monoxide

Carbon monoxide

A masonry structure built below ground level, where biochemical reaction takes place due to anaerobic bacteria is called cesspool lagoon skimming mill septic tank

septic tank

A considerable part of the harmful ultraviolet radiation of the sum does not reach the earth surface, because of the fact that, there is a layer of __________ high above earth's atmosphere, which absorbs it. hydrogen carbon dioxide ozone none of these

ozone

White smoke coming out of the chimney of a furnace indicates the use of low excess air. very high excess air. gaseous fuel in the furnace. liquid fuel in the furnace.

very high excess air.

TLV of NO2 & NO exposure for the human being is 5 & 25 ppm respectively. Prolonged exposure of human being to NO2 causes skin disorder bronchitis bone disease cancer

bronchitis

Sulphur dioxide present in the industrial chimney exhaust gases causes respiratory & lung disease. reduction in plant's productivity owing to acid rain. corrosion of building materials. all (a), (b) and (c).

all (a), (b) and (c).

A man exposed to excessive noise level in the working environment may suffer from hearing loss rupture of ear drum nervousness & fatigue all (a), (b) & (c)

all (a), (b) & (c)

Which of the following is a secondary air pollutant ? Photochemical smog Sulphur dioxide Nitrogen dioxide Dust particles

Photochemical smog

Presence of __________ bacteria in water causes disease like typhoid. aerobic pathogenic anaerobic non-pathogenic

pathogenic

CFC (chloro fluoro carbon) is very highly reactive in causing depletion of ozone layer in the atmosphere. Each atom of chlorine liberated from CFC is capable of decomposing __________ molecules of ozones. 102 105 109 1015

105

Green house gases blanket/block the infrared radiation from earth's surface to the atmosphere leading to its progressive warming up. Which of the following gases does not exhibit green house effect ? CO2 H2 SO3 N2

SO3

A 'body' which allows the short wavelength incoming solar radiation to enter in, but does not allow long wave length outgoing infra red radiation to escape out is called the global warming green house atmospheric effect ionosphere

green house

Fresh domestic sewage is __________ in color. grey dark brown red black

black

The common pollutant generated in chlor-alkali industry and battery manufacture is mercury brine phosphate none of these

mercury

During sewage treatment, the sewage is subjected to __________ treatment in Imhoff tank. filtration digestion sedimentation both (b) and (c)

both (b) and (c)

Black smoke coming out of the chimney of a furnace is an indication of the use of __________ in the furnace. low amount of excess combustion air large quantity of excess combustion air hydrocarbon fuel pulverised coal as fuel

low amount of excess combustion air

Pick out the wrong statement. A slight haze at the top of chimney indicates good combustion in the furnace. A bag filter incurs very small pressure drop and is very efficient for removal of sub-micronic dust particles from flue gases at very high temperature. Electrostatic precipitator is the most efficient dust collection equipment for removal of sub-micronic dust particles present in flue gas. none of these.

A bag filter incurs very small pressure drop and is very efficient for removal of sub-micronic dust particles from flue gases at very high temperature.

__________ content of the phosphate rock is the pollutant of primary interest in a phos-phatic fertiliser plant. Calcium Fluorine Phosphorous Sulphur

Fluorine

Beyond what concentration of H2S in air, acute danger to human life exists ? 50 ppm 100 ppm 300 ppm 700 ppm

700 ppm

Reingleman chart is used for the evaluation of __________ pollution. air water noise radioactive

air

There are five concentric layers within the atmosphere which is differentiated on the basis of temperature. The atmospheric layer which lies close to the earth's surface in which human being along with other organisms live is called troposphere. The rate at which air temperature in the troposphere gradually decreases with height is about __________ °C/km. 0.05 1 6.5 15

6.5

Brown spots in fabrics will be caused by washing with water containing large amount of . iron zinc iodine bromine

iron

Maximum permissible concentration (i.e. TLV) of DDT in public water supply system is __________ micro gram (μ g)/litre. 2 42 332 1050

Sooty and sulphurous smog formed due to combustion of fossil fuels particularly in winter, continues throughout the day and night. When the moist atmospheric air's water vapor condenses on the solid particles of smoke thereby forming smog (smoke + fog), it causes poor visibility due to sky darkening. irritation in eyes. respiratory trouble. all (a), (b) and (c).

all (a), (b) and (c).

Deaeration of high pressure boiler feed water is done to reduce foaming from boilers. its dissolved oxygen content. its silica content. caustic embrittlement.

its dissolved oxygen content.

Exposure to SO2 containing chimney gases results in the reduction in strength of leather & cloth. acceleration of corrosion rates of metals. increased drying & hardening time of paints. all (a), (b)and(c).

all (a), (b)and(c).

The detrimental effect on organism and water quality with temperature rise of aquatic system is the reduction of __________ of water. dissolved oxygen content biological oxygen demand vapor pressure all (a), (b) and (c)

dissolved oxygen content

Hydrogen ion concentration in distilled water is 10-7 7 x 10-7 107 7 x 107

10-7

Out of the following, TLV of __________ is maximum (about 500 ppm). carbon dioxide toluene carbon disulphide acetaldehyde

carbon dioxide

Which of the following plants does not emit appreciable amount of SO2 in atmosphere ? Thermal power plant Petroleum refinery Nitric acid plant Sulphuric acid plant

Nitric acid plant

The maximum CO2 is emitted into the atmosphere by combustion urea biomass burning trees

combustion

Which of the following is not a practical method of low level radioactive waste disposal ? Dilution with inert material. Discharging to atmosphere through tall stacks after dilution. Disposing off in rivers & oceans. Filling in steel crates and shooting it off out of earth's gravity.

Filling in steel crates and shooting it off out of earth's gravity.

Major sources of noise in furnace operation arises from air inspirators, combustion, side wall vibrations and fluctuation in the process heat load. A 50% increase in fuel firing rate may increase the furnace noise level by about __________ decibels. 3 30 70 100

Removal of __________ results from the disinfection of water. turbidity odour hardness bacteria

bacteria

Very small amount of air pollutants are present in stratosphere also; though most of the atmospheric pollutants are present in the troposphere. Which of the following atmospheric pollutants does not cause the ozone layer depletion in atmosphere at tremendous rate ? CO SO2 NOx CFC (chloro fluoro carbons)

Carcinogenic air pollutants cause bone decay cancer asphyxiation (suffocation) anemia

cancer

Inhalation of silica dust by human being during hand drilling in mica mining, lead & zinc mining, silica refractory manufacture and in foundaries causes asphyxiation (suffocation). shortness of breath. tuberculosis. all (a), (b) and (c).

all (a), (b) and (c).

Soluble silica present in boiler feed water can be removed by coagulation filtration anion exchanger preheating it

anion exchanger

Presence of non-biodegradable substances, like alkyl benzene sulphonate (ABS) from the detergents in polluted water stream causes fire hazards. explosion hazards. persistent foam. depletion of dissolved oxygen.

persistent foam.

Pick out the wrong statement. The concentric layer in atmosphere which contains about 70% of the total mass of atmosphere and characterised by a steady decrease in temperature is called stratosphere. Stratosphere is rich in ozone and is located just above the troposphere. Troposphere is a turbulent dusty zone containing much of water vapor and clouds. The earth's atmosphere is an envelope of gases extending upto a height of about 200 kms.

The concentric layer in atmosphere which contains about 70% of the total mass of atmosphere and characterised by a steady decrease in temperature is called stratosphere.

Radioactive solid nuclear wastes are disposed off by high temperature incineration. pathological incineration. pyrolysis. underground burial in concrete containers.

underground burial in concrete containers.

Growth of __________ is promoted by the presence of manganese in water. files algae micro-organisms mosquitoes

micro-organisms

Average human body contains about __________ percent water by weight. 20 40 70 85

Noise level audible to audience sitting in the 5th row from the stage during a large orchestra show corresponds to about __________ decibels. 105 135 160 185

135

If carbon monoxide content in atmospheric air exceeds __________ ppm, death is bound to occur. 50 500 1000 3000 (i.e. 0.3%)

3000 (i.e. 0.3%)

Envi Engg Flashcards

(307 cards)