UNIT#01 INTRODUCTION TO FUNDAMENTAL CONCEPTS OF CHEMSITRY Flashcards
(535 cards)
1
Q
How many unstable radioactive isotopes have been produced through artificial disintegration:
A
300
2
Q
The total types of fundamental nuclear sub-atomic particles are there in an atom:
A
2
3
Q
Isotopes are:
A
Chemically Similar
4
Q
Molecular ions are formed by passing:
A
➡High energy electron beam
➡α-Particle
5
Q
A number of moles present in 0.6 g of silica are:
A
0.01 mole
6
Q
Volume occupied by 4.4 g of CO2 at STP is:
A
2.24 dm³
7
Q
Which one is the molar volume of gas at STP?
A
22.4 dm³
8
Q
Number of H+ ions when 0.1 mole of sulphuric acid is completely ionized in water;
A
2 x 6.022 x 10²²
9
Q
How many electrons have to be removed to ionize 1.0 x 10-⁶ moles of Ne atoms to Ne+ ions in a neon advertising tube
A
1.0 x 10-⁶ x 6.022 x 10²³
(No. of electron= n x NA)
10
Q
When 0.5 moles of Al2(SO4)3 are dissolved in water, a total number of particles produced:
A
1.5 x 10²⁴
11
Q
Which of the following contains 1 mole of particles?
A
Electrons in 1 g of hydrogen gas
12
Q
The number of moles of CO2 which contain 16 g of oxygen
A
0.50
13
Q
The mass of one molecule of O2 is;
A
32 / 6.022 x 10²³ g
14
Q
Amount of oxygen in grams which contains 1.5 x 10²² molecules:
A
40g
(no. of particles = no. of moles x NA)
15
Q
A number of electrons in half a mole of Na+:
A
5 NA
16
Q
3 x 10-²¹ moles of an amino acid having a molecular mass of 200 g mol-1, would have molecules:
A
1800 molecules
17
Q
The relative atomic mass of oxygen is 16 amu. What is the mass of 2 moles of oxygen gas?
A
64 g
18
Q
Which of the following has maximum mass?
A
25 g mole of water
19
Q
The mass of one mole of chlorine gas is:
A
71 g
20
Q
Which of the following is not true for one mole?
A
➡It is counting units ❌
➡It is the gram atomic or gram formula mass of a substance❌
➡It contains 6.02 x 10^23 particles❌
➡It contains a different number of particles for different substances✅
21
Q
During combustion analysis, which one is used for absorbing carbon dioxide
A
50% KOH solution
22
Q
Absorption of CO2 in KOH solution during combustion analysis is:
A
Chemical change
23
Q
Which of the following compounds has the highest percentage of oxygen by weight:
A
H2O
(Depends on molecular mass)
24
Q
Which of the following compound have an empirical formula, but no molecular formula:
A
NaCl
(Ionic Compounds do not have molecular formulas)
25
The sole products of combustion analysis are;
➡CO2
➡H2O
26
An acid with molecular mass 104 contains 34.6%C, 3.85%H and the rest are O. The molecular formula for acid is:
C3H4O4
27
6Na + Fe2O3 ➡ 3Na2O + 2Fe
For the above reaction, if you are provided with 230g Na ad 320g Fe2O3, then the limiting reactant is;
Na
28
Mg reacts with HCl as per the following reaction:
Mg + 2HCl ➡MgCl2 + H2
Given that; Mg=21g and HCl= 21g, then the excess reactant is:
Mg
29
What volume of oxygen is required for complete combustion of 5cm³ of C2H2
12.5 cm³
30
11.201 dm³ of methane at STP has _____ moles of hydrogen atoms
0.5
31
How much Al is required to form alumina with 12g of oxygen
13.5 g
32
The actual yield is always less than the theoretical yield due to;
➡Side Reaction
➡Reversible Nature
➡Mechanical Loss
33
Indicate the incorrect statement from the following:
➡A limiting reactant is consumed at the end of the reaction❌
➡Actual Yield is always greater than the theoretical yield✅
➡Stoichiometric calculation can be only done if no side reaction happens❌
➡The empirical formula and molecular formula of some the compounds are same❌
34
The calculation of the efficiency of a chemical reaction can be checked by knowing the amount of:
The product formed
35
When one mole of each of the following is completely burnt in oxygen, which will give the largest mass of CO2:
Ethane
36
If we know the mass of one substance, we can calculate the volume of another substance and vice versa with the help of a chemical equation called;
Mass-Volume Relationship
37
With the help of spectral data given calculate the mass of Neon and encircle the best option:
20.18 amu
(Relative atomic Mass = (atomic number x percentage) + (atomic number x percentage) / 100
38
How many chlorine atoms are in 2 moles of Cl:
2 x 6.022 x 10^23 atoms
39
1 amu is equal to;
1.661 x 10-²⁷ kg
40
how much volume of O2 is required or formation of SO3 from 0.222 moles of SO2:
2.24 L
41
The number of single covalent bonds in water molecules are:
2
42
Ascorbic acid has a high percentage of:
Oxygen
43
NH3 can be called:
Molecule of compound
44
The diameter of an atom is;
0.2 nm
45
No side reaction takes place in:
Stoichiometry
46
NH3Cl and Ca(OH)2 react to form ammonia. What is the mass of ammonia produced when 100 grams of each is given:
31.7 g
47
The mass present in 2 dm³ of O2 at STP:
2.8
48
The product of combustion of H2 is;
H2O
49
A mole of N in 2g of N2;
1/14
50
Chemical equations do not tell about the ___ because of certain limitations.
➡Rate of reaction
➡Conditions
➡Pressure
51
An ordinary microscope can measure the size of an object up to or above;
500 nm
52
18 g of water contains ____ atoms of hydrogen:
2 x 6.02 x 10²³
53
The relative atomic mass of copper is;
63.55 amu
54
25 cm³ of the sample of H2 gas effuses four times as rapidly as 25 cm³ of an unknown gas what will be the molar mass of unknown gas:
32 g/mol
55
The negative ions having a group of atoms is/are:
➡OH-
➡CO3-²
➡Cr2O7-²
56
The study of the composition of pure substances in the 17th century clearly shows that few elements are components of many substances:
Quantitative
57
The concept of ____ gases helps to relate solids and liquids in a quantitative manner.
Molar Volume
58
The empirical formula of ascorbic acid is:
C3H4O3
59
NH3 gas can be prepared by heating together solid NH4Cl and Ca(OH)2, if a mixture containing 100g of each solid is heated, then calculate the mass of ammonia:
31.7 g
60
In combustion analysis, CO2 is absorbed by:
50% KOH
61
If we know the mass of one substance, we can calculate the volume of another substance and vice versa with the help of a chemical equation called:
Mass-Volume Relationship
62
One mole of any gas at STP occupies a volume of;
22.414 dm³
63
How many chlorine atoms are in 2 moles of Cl;
2 x 6.022 x 10²³ atoms
64
An organic compound has the empirical formula C3H3O if the molar mass of the compound is 110.15 molecular formula of this organic compound is:
C6H6O6
65
When 8 grams (4moles) of H2 react with 2 moles of O2, how many moles of water will form;
Four
66
Hydrogen burns in chlorine to produce hydrogen chloride. The ratio of masses of reactants in chemical reaction H2 + Cl2 ➡2HCl is:
1:35.5
67
A polymer of the simplest formula CH2 has molar mass of 28000 g/mol. Its molecular formula would be;
2000 times than its empirical formula
(n=Molecular Formula Mass/Empirical Formula Mass)
68
The number of molecules in 9g of ice is;
3.01 x 10²³
69
How many moles of sodium are present in 0.1 g of sodium?
4.3 x 10-³
70
An organic sample consisting o carbon, hydrogen and oxygen was subjected to combustion analysis. 0.5439 g of this compound gave 1.0039 g of carbon dioxide, and 0.6369 g of water vapours. The empirical formula of this compound is:
C2H6O
71
The number of moles of CO2 containing 8.00 g of oxygen is:
0.25
72
A researcher has prepared a sample of 1-Bromopropane from 10g of 1-propanol. After purification, he made 12 g of product. Which of the following is the percentage yield?
58%
73
Which one of the following has the same number of molecules as present in 11g of CO2:
4.5 g of CO2
74
Choose the correct option regarding the number of particles associated with one mole of a substance:
6.02 x 10²³
75
Determinate the number of moles of O in 10.6 g of Na2CO3:
0.2 moles
76
Calculate the gram of H2O formed when 8g of CH4 burns in excess of oxygen:
18 grams
77
While finding the relative atomic mass, which of the following standard is used to compare the atomic mass of chlorine;
Carbon-12
78
The formula shows the simplest whole number ratio for the atoms of different elements in a compound:
Empirical Formula
79
3.0 mole of calcium will contain ____ g of calcium.
106.5g
80
The average atomic mass of Boron is 10.8. It has two isotopes of masses 10 and 11 respectively. What is the percentage of isotopes with an average mass of 10?
20%
81
The best standard for the calculation o relative atomic mass:
Carbon-12
82
A piece of diamond embedded in a gold ring weighs 6.0 g. How many moles of Carbon does it contain;
0.5 mole
83
Iron is manufactured industrially in blast furnaces using Hematite (an iron of ore) and a reducing agent Carbon Monoxide.
Fe2O3 + 3CO ➡2Fe + 3CO2.
Calculate the mass of iron ore used to manufacture 56 g of iron with excess carbon monoxide. Assume that the process gives 100% yield.
80 g
84
How many moles of calcium carbonate is present in 1.75 kg of calcium carbonate?
17.5 mole
85
According to the law of definite proportion, what is the mass ratio of hydrogen and oxygen in water?
➡Hydrogen is 11.11%
➡oxygen is 88.89%
86
How many oxygen atoms are present in 278g of Hydrated Ferrous sulphate?
6.525 x 10²⁴
87
The water formed in the combustion analysis is usually absorbed by
Mg(ClO4)2
88
Which contains the highest percentage of Nitrogen?
N2O
(%age of Element = Mass of Element/ Molar Mass of compound x 100 )
89
A mixture of 10cm³ of oxygen and 50 cm³ of hydrogen is sparked continuously. What is the maximum theoretical decrease in volume?
30 cm³
90
The number of moles of water in 1 kg of ice is;
55.5 moles
91
During stoichiometric calculations. which of the following laws must be followed?
Law of conservation of mass
92
The efficiency of a chemical reaction can be expressed as:
% yield
93
In a vessel, 10g of N2, 10g H2 and 10g O2 are present. Which one will have the least number?
O2
94
The empirical formula of glucose is:
CH2O
95
Which of the followign sets contains only compounds?
➡Carbon Monoxide
➡Phosphine
➡Phosgene
96
Which of the following has highest atomicity?
Sulphur
S8
97
Which one of the following pair is isoelectronic:
➡H2O
➡Ne
98
Which of the following statements is true about isotopes.
They have same number of electrons
99
Which of the following set of elements form nearly 50% of earth crust.
➡O
➡Mg
➡Si
➡Ca
➡Fe
100
At present total number of non-radioactive isotopes occur in nature:
240
101
Atomic mass unit (a.m.u) is equal to;
Mass of one proton
102
20 amu of neon is:
Relative isotopic mass
103
Which pair of elements have same number of isotopes?
➡B
➡Cl
104
Which one of the following has maximum number of isotopes?
Cd
105
1 mole of different gases have different :
Molar Masses
106
A pair that have same number of particles:
➡32 g O2
➡32 g N2H4
107
Equal volumes of N2O and CO2 are taken in ideal conditions, the correct relation between the masses of two gases is:
N2O = CO2
108
How many moles of neutron are present in one mole of heavy water?
10
109
15 gram of a gas occupies 11.2 dm³ at S.T.P, the gas is;
NO
(Volume/Molar Volume = Mass/Molar Mass)
110
Maximum number of molecules will be in:
44 g of CO2
111
A pair that have same number of moelcules: :
➡32g O2
➡32g N2H4
112
Equal volumes of N2O and CO are taken in identical conditions, the correct relation between the masses of two gases is:
N2O = CO2
113
The volume of oxygen gas is 1.12 dm3 at STP, the mass of oxygen is approximately:
1.6 g
114
The molar volume of a gas depends upon its:
Pressure
115
Which of the following term is not used for ionic compounds?
Molecular Formula
116
Which one of the following statements is not involved in the determination of empirical formula
Isotopes of each element
117
For which of the following compounds, the term empirical formula cannot be applied:
➡NaCl
➡H2O
➡CCl4
118
The value of "n" in determining molecular formula is obtained from the relation:
n = molecular ,mass/ empirical formula mass
119
An unknown compound has empirical formula CH3O. Its molar mass is 62g/mole. The compound may be;
CH2(OH)CH2(OH)
(n=62/31=2
Molecular Formula = 2 x CH3O)
120
While determine molecular formula, the simple multiple "n" is not unity for:
H2O2
121
An acid with molecular mass 104 contains 34.6%C, 3.85%H and rest is O. The molecular formula of acid is;
C3H4O4
122
A compound contains 50% S and 50% O by mass. The empirical formula of compound is;
SO2
123
A pair of compounds that has same empirical formula:
➡Acetic acid
➡Glucose
124
The simplest formula of a compound containing 50% of element X (Atomic Weight= 10) and element Y (Atomic Weight=20)
X2Y
125
The number of OH- ions required to react completely with H+ ions produced by 100% dissociation of 49g H3PO4
9.03 x 10²³
126
Which one act as a limiting reactant when 6 g of carbon and 16g of oxygen react to produce CO2
None of these
127
21g of CaO is obtained by roasting 50g CaCO3. What is the percentage yield of CaO?
75%
128
For stoichiometry calculations, we have to assume
All the reactants are completely converted into products
129
If a sample of ammonium phosphate, (NH4)3PO4 contains 6 moles of hydrogen atoms. Then number of moles of oxygen atoms in the sample is:
2
130
The law of conservation of mass and the law of definite proportions are obeyed while doing calculation of;
➡Limiting Reactant
➡Theoretical Yield
➡Stoichiometry
131
How many moles of potassium chlorate should be decomposed completely to obtain 67.2 dm³ of oxygen at STP?
2
132
"X" gram of carbonate was completely burnt in air as. The weight of solid residue formed is 14g. What is value of "X" in grams.
25
133
The relation which works best in stoichiometry
Mole-Mole
134
A ring studded with diamond which weighs 3g. The number of carbon atoms in the diamond are:
1.5 x 10²³
135
Hydrogen and oxygen have same at STP?
Gram Molecular Volume
136
Total ion in 5 formula units of NaClO3 is equal to the number of:
10 electrons in Neon
137
The total number of atoms in 10g of calcium carbonate
3.01 x 10²³
138
The number of atoms in 16g Ozone is approximately:
6 x 10²³
139
Which of the following sample conatins the largest number of atoms?
1g of B
140
The number of moles of CO2 which contains 16g of oxygen
0.50
141
Stoichiometric caclulation assume that;
➡All the reactants are completely converted into product
➡No side reaction occurs
➡In calculation, law of conservation of mass and law of definite proportions are obeyed
142
0.36 moles of aluminum and oxygen each react to produce alumina then which of the following is limiting reactant and non-limiting reactant respectively:
Al ➡ Limiting Reactant
O2 ➡ Non-Limiting Reactant
143
A sample of CaCO3 has Ca=40%, C=12% and O= 48%. If the law o constant proportions s true, then the mass of Ca in 5g of CaCO3 will be:
2.00g
144
The atom of which element can exist independently
Helium
145
Hemoglobin moelcule is ___ times than heavier H2:
34,000
(Hemoglobin moelcule is 68,000 times than heavier hydrogen atom)
146
The atomicity of haemoglobin is;
10,000
147
An atom of carbon is twelve times heavier than ____ atom.
He
148
An electron is:
A subatomic particle
149
Total ions in 5 formula units of NaClO3 is equal to the number of:
10 electrons in Neon
150
CN-1 is iso-electronic with;
CO
151
Which of the following term is used or the mass of chlorine 35.5 amu
Realtive atomic mass
152
Which pair of elements have same number of isotopes
➡Palladium
➡Calcium
153
Which one of the following has the maximum number of isotopes?
Tin
10 isotopes
154
Out of 280 isotopes that occurs in nature, ____ have even mass number and even atomic number.
154
155
A pair of compunds that has same empriical formula:
➡Acetic acid
➡Glucose
156
Which is correct statement:
Quantitative analysis involves four steps
157
A compound used as artificial sweetener has formula:
C14H18N2O5
158
An acid with molecular mass 104 contain 34.6%C, 3.85%H and rest is O, the moelcular formula of acid is:
C3H4O4
159
There are different steps in determining the empirical formula
Step I. Calculating the number of gram atom
Step II. Determining the atomic ratio
Step III. Determining the percentage composition
What is the correct sequence of the above steps:
III, I, II
160
The simplest formula of a compound containing 50% of element X (At.wt=10) and 50% of element (At.wt = 20) is;
X2Y
161
A compound with empirical formula CHO2 and molecular mass 90g/ mole. The molecular formula of the compound is;
(COOH)2
162
CH2O is the empirical formula of:
CH3COOH
163
An unknown compound has empirical formula CH3O. Its molar mass is 62g/mol. The compound may be:
CH2(OH)CH2(OH)
164
3.0 g of NO gas occupies volume;
2.2414 dm³
165
Which one of the following contains least number of molecules?
16.0 g SO2
166
One mole of H2SO4 contains:
2.4088 x 10²⁴ atoms of oxygen
167
Which one has maximum number of atoms:
1g Mg
168
1 mole of CH3OH and C2H5OH have equal number:
O-Atoms
169
Which of the following has same number of moles?
➡15g of C
➡30g of Mg
170
The number of hydrogen atoms in 36g of NH4+¹ is approximately:
8 NA
171
0.5 mole of H2O is formed when 1 mole H2 reacts with ____ g of O2:
8
172
Which one is incorrect relation at STP?
➡6g of carbon = 3.01 x 10^23 atoms❌
➡11.2 dm^3 of CO2 = 3.01 x 10^23 molecules❌
➡49g of H2SO4 = 4 moles of atoms✅
➡1 mole of sucrose = 45 moles of atoms❌
173
The total number of O-atoms in 18g of glucose are:
3.6 x 10²³
174
Which of the following terms is used for 238 g of uranium:
1g atom
175
When 0.5 mole of phosphoric acid is dissolved in aqueous solution how many moles of -ve and +ve ions are collected altogether :
2.0
176
Avogadro's Number is the number of molecules present in;
Gram Molecular Mass
177
How many chlorine atoms are in 4 moles of Cl2:
8 x 6.022 x 10²³ atoms
178
What is the volume (in dm³) of CO2 liberated at STP, when 53 gram of sodium carbonate (molecular mass=106) is treated with excess dilute HCl in following reaction
11.2
179
One mole each of NO2 and CO2 has same number of:
Molecules
180
Avogadro's number of particles of hydrogen gas weighs:
2.016 g
181
Volume occupied by 7g of N2 present in a mixture:
5.6 dm3
182
1.4 g atom of nitrogen at STP represents:
2.24 dm³ of N2
183
The weight of 11.2 dm³ of CO2 at STP would be:
22 g
184
3 x 10-²¹ moles of an amino acid having molecular mass 200g/mole would have molecules:
1800
185
2.24 dm³ of CO2 gas at S.T.P has mass:
4.4 g
186
Block of metals Mg, Al, Fe, Zn of each mass 100g. The maximum number of atoms present in a block of metal.
Mg
(As Mg has the smallest atomic mass)
187
180 g of glucose contain number of hydrogen atom
7.2 x 10²⁴
188
The study of quantitative relationship between reactants and products in a balanced chemical equation is known as:
Stoichiometry
189
Which type of relationship can be studied with the help of a balanced chemical equation:
➡Mass-Mass relationship
➡Mole-Mass relationship
➡Mass-Volume relationship
190
For stoichiometry calculations, we have to assume:
All the reactants are converted into products
191
0.5 mole of H2O is formed when 1 g H2 reacts ___ g of O2.
8
192
Balance chemical equation tells us about:
Direction of reaction
193
What mass of calcium carbonate in grams is required to produce 5.6 dm³ of CO2.
25 g
194
Mass of an atom of C is;
➡12/NA
➡12 amu
➡12 x 1.661 x 10-²⁴ g
195
1 gram molecule refers to amount in grams.
Equivalent to 1 mole of a molecule
196
1 gram formula refers to;
Amount in grams equivalent to 1 mole of an ionic compound
197
One mole of SO2 contains:
6022 x 10²³ atoms of sulfur
198
The mass of 1 mole of magneisum atoms is 24g. What is the mass of one magnesium atom in grams?
3.99 x 10²³
199
The approximate number of molecules present in 3g of H2O is:
1 x 10^23
200
The largest number of molecules are present in:
3.6g of H2O
201
40g of calcium is:
1 gram atom of Ca
202
How many atoms of carbon are present in 34.2 g of sucrose
7.2 x 10^23
203
If a ring is made up of 6g of diamond, the number of atoms present in it are:
3.01 x 10^23
204
Moles of protons in 20g of SO3:
10
205
The mass of 10^-3 moels of MgSO4 is:
0.12 g
206
Which of the following contains the same number of atoms as 12g of Mg
10g of Neon
207
Equal volumes o CO and N2 are taken in identical conditions, the correct relationship between masses o two gases is:
CO=N2
208
The most significant number of molecules are present in:
36g of H2O
209
The Avogadro's number of atom or molecules or formula are units of a substance is called its:
Mole
210
Which of the following quantity is not 1 mole;
➡1 g of an element❌
➡1 g formula of an ionic compound❌
➡1 atomic mass unit✅
➡1 g molecule of a covalent compound❌
211
18.02 g of H2O:
6.022 x 10^23 molecules of H2O
212
A unit which represents 6.02 x 10^23 particles is called:
➡Mole
➡1 gram molecule of nitrogen
➡1 gram ionic mass
213
% of nitrogen in urea (NH2CONH2):
46.6%
214
A compound contains 50% sulphur and 50% of oxygen by mass. The empirical formula of the compound is:
SO2
215
The empirical formula of vitamin C (Ascorbic Acid) is:
C3H4O3
216
If the empirical formula of a compound is CH2 and its molecular mass is 56 amu. What will be its molecular formula?
C4H8
217
Molecules formula = n x empirical formula
Which statement is correct about "n"
It can never be zero
218
Styrene has the empirical formula CH, and there is 92.2 % C and 7.75% hydrogen. if the molar mass is 104g/mol, what will be the integral multiple (n) to get the molecular formula
8
219
Combustion analysis is performed for the determination of:
The empirical formula of the compound
220
The stoichiometric calculations for a chemical reaction results in:
Theoretical yield
221
5603 cm^3 of hydrogen gas at STP contains atoms of hydrogen.
3.01 x 10^23
222
Gram atoms of hydrogen in 5.5 g H2
5.50
223
4g of an unknown gas occupies 5.6 dm^3 volume, at S.T.P the gas is;
CH4
224
10 moles of HCl are added to excess magnesium and form 4 moles of hydrogen gas percentage yield is:
80%
225
Which of the following is a limitation of a balanced chemical equation:
➡Conditions and Rate of Reactions
➡Physical state and Mechanism
226
How much oxygen is required to react 16g of S to form SO2
16g
227
If the actual yield of a product is 8g, then the theoretical yield will be ____ while the reaction is 80% efficient.
10g
228
4 moles of hydrogen react with 5 moles of oxygen to form water, and identify the excess reagent:
Hydrogen
229
If 15g of sulphur is burnt, what volume of SO2 is produced at STP?
10.51 dm^3
230
If you have 3.5 moles of hydrogen and 5 moles of nitrogen to produce ammonia. How much ammonia is produced
39.6 g
231
Which of the following conditions of temperature and pressure are the standard conditions?
➡0°C and 1 atm pressure
➡273K and 14.7 PSI
➡32°F and 760 torr
232
Which one is the experimental equation:
➡Rate equation
➡Rate expression
233
2.8 g of N2 molecules contain number o chemical bonds:
1.8 x 10^23
234
A limiting reactant is one which;
Gives minimum amount of product under consideration
235
An acid with molecular mass 104 contains 34.6%C, 3.85% H and the rest are O. The molecular formula of acid is;
C3H4O4
236
The total number of atoms in 9g of water are;
9.03 x 10^23
237
One-gram molecules of different gases have all the following properties same at STP except:
Masses
238
A pair that have the same number of molecules;
➡32 g O2
➡32 g N2H4
239
One mole of which of the following will have a different number of electrons than others
CO+1
240
The total number of O-atoms in 18g of glucose are:
3.6 x 10^23
241
21 g of CaO is obtained by roasting 50g of CaCO3. What is the percentage yield of CaO?
75%
242
The absorption of CO2 in 50% KOH leads to:
Chemical Change
243
A sample of 100cm^3 of dilute H2SO4 contains 0.1 moles of acid. What is the hydrogen ion concentration in the solution per dm^3?
2 moles
244
The number of moles of KMnO4 that contain 1 mole of the oxygen atom
0.25 moles
245
A pair of compounds that has the same empirical formula
➡Acetic acid
➡Glucose
246
Elemental analysis is performed to determine:
The empirical formula of a compound
247
Hydrogen and oxygen have the same at STP
Gram molecular volume
248
Equal volumes of N2O and CO2 are taken in identical conditions, the correct relation between the masses of two gases is:
N2O = CO2
249
Which one has the maximum number of atoms
1g Mg
250
Which one will produce the largest number of negatively charged ions in case of 100% dissociation of 1 mole.
FeCl3
251
1 mole of CH3OH and C2H5OH have an equal number
O-atoms
252
Mass spectrometry is used to determine the:
➡Number of isotopes of an element
➡Relative abundance of isotopes
➡Relative isotopic masses
253
The stoichiometric calculations or a chemical reaction results in:
Theoretical Yield
254
1 gram molecule refers to the amount in grams
Equivalent to 1 mole of a molecule
255
A number of H+ ions when 0.1 moles of sulfuric acid is completely ionized in water:
2 x 6.022 x 10^22
256
1 gram formula refers to:
Amount in grams equivalent to 1 mole of an ionic compound
257
How many electrons have to be removed to ionize 1.0 x 10^-6 moles o Ne atoms to Ne+ ions in a neon advertising tube
1.0 x 10^-6 x 6.02 x 10^23
258
One mole of SO2 contains:
6.022 x 10^23 atmos of sulfur
259
56.4 cm^3 of H gas at STP contains atoms of hydrogen:
3.01 x 10^23
260
The number of moles present in 0.6 grams of silica is:
0.01 mole
261
Gram atoms of hydrogen in 5.5g H2
3.01 x 10^23
262
% of nitrogen in urea(NH2CONH2)
46.6%
263
One mole of potassium chlorate is thermally decomposed and an excess aluminium is burnt in a gaseous mixture. how many moles of aluminium oxide are formed?
2KCLO3 ➡KCl + 3O2
4Al + 3O2➡2Al2O3
1.0
264
In a mass spectrometer, increasing the electric field with constant magnetic field results in:
decreased radius "r"
265
When 0.5 models of Al2(SO4)3 are dissolved in water, the total number of particles produced
1.5 x 10^24
266
The mass of one mole of magnesium atoms is 24g. What is the mass of one magnesium atom in grams?
3.99 x 10^-23
267
Which of the following contains 1 mole of the stated particles
Electrons in 1g of hydrogen gas
268
During combustion analysis, which one is used for absorbing carbon dioxide:
50% KOH solution
269
Which one is the mono-isotopic element:
Fluorine
270
Molecular ions are produced in mass spectrometers. Which type of molecular ions formed more abundantly
Positively charged
271
The height of the peak in the mass spectrum shows:
Relative abundance
272
The separation of different isotopes in the mass spectrometer is done on the basis of:
different m/e
273
A compound contains 50% sulfur and 50% oxygen by mass. the empirical formula of the compound is;
SO2
274
Equal volumes of CO and N2 are taken in identical conditions. The correct relationship between the masses o two gasses is:
CO=N2
275
The approximate number of molecules present in 3g of H2O is:
1 x 10^23
276
The mass of one molecule of O2 is:
32/6.02 x 10^23
277
Combustion analysis is performed for the determination of:
The empirical formula of the compound
278
1 amu is equal to:
1.66 x 10^-21 mg
279
A haemoglobin molecule is how many times heavier than a helium atom
17000
280
Which of the following is a pure substance
Distilled Water
281
How many isotopes are preset in palladium
Four
282
Naturally occurring isotopes of silver are
Two
283
Atoms having the same mass number but different atomic numbers are called:
Isobars
284
40g of calcium is:
1 gram atom of Ca
285
Amount of oxygen in grams which contains 1.5 x 10^22 molecules
0.80
286
What volume of oxygen is required for complete combustion of 5cm^3 C2H2
12.5 cm^3
287
How many atoms of carbon are present in 34.2g
1.2 x 10^22
288
Absorption of CO2 in KOH solution during combustion analysis is:
Chemical cHange
289
10 moles of HCl are added to excess magnesium and form 4 moles of hydrogen gas percentage yield is;
80%
290
If you have 3.5 moles of hydrogen and 5 moels of nitrogen to produce ammonia. How much ammonia is produced
39.6 g
291
How many unstable radioactive isotopes have been produced through artificial disintegration
300
292
The empirical formula for vitamin C is:
C3H4O3
293
Number of electrons in half a mole of Na+
5.5 NA
294
The amount of products obtained from the balanced chemical equation represents
Theoretical yield
295
Which of the following compounds has the highest percentage of oxygen by weight:
CH3OH
296
The volume occupied by 4.4 g of CO2 at STP is:
1122 cm^3
297
If a ring is made up of 6g diamond, then a number of atoms present in it are:
1.5 x 10^23
298
Which of the following has the least mass
1 mole of Neon gas
299
If the empirical formula of a compound is CH2 and its molecular mass is 56 amu. What will be its molecular formula?
C4H8
300
Which of the following compound have an empirical formula, but no molecular formula?
NaCl
301
Moles of protons in 20g of SO3
10
302
Which of the following is a limitation of a balanced chemical equation
➡Conditions and Rate of Reaction
➡Physcial State and Mechanism
303
3 x 10^-21 moles of an amino acid having a molecular mass of 200 g mol-1, would have molecules
1800
304
Molecules formula = n x (empirical formula), which statement is correct about 'n'
it can never be zero
305
11.207 dm^3 of methane at STP has _____ moels o hydrogen atoms.
2
306
The element showing 100% abundance in the mass spectrum is;
Arsenic
307
Which of the following isotopes will have maximum deflection in magnetic field during mass spectrometric analysis:
C-12
308
Which of the following contains the same number of atoms as 12g of Mg?
10 g Neon
309
Which is a molecular ion
NH3+
310
The sole products of combustion analysis are:
➡CO2
➡H2O
311
Styrene has the empirical formula CH, and there are 92.2% and 7.75% hydrogen. If the molar mass is 104 g /mole, what will be the integral multiple(n) to get the molecular formula
8
312
An acid with molecular mass 104 contains 34.6%C, 3.85%H and the rest are O. The molecular formula of acid is:
C3H4O4
313
How much oxygen is required to react 16g of S to form SO2
16 g
314
How much Al is required to form alumina with 12g of oxygen?
13.5 g
315
An element X has two isotopes X-35 and X-37 with an average atomic mass of 35.5 amu. Relative abundance of bot isotopes is repsectively
➡75%
➡25%
316
An element has two isotopes A-63 and A-64 with an average atomic mass of 63.5 amu. The relative abundance of lighter isotopes is;
50%
317
At STP a gas which has maximum value;
4 g of H2
318
The negative ion having group of atom is/are:
➡OH-
➡CO3-2
➡Cr2O7-2
319
The term relative atomic mass is used for:
35.5 amu Cl
320
All elements of the periodic table chemically differ from each other due to:
Atomic Number
321
The correct relation between empirical formula and molecular formula is:
Empirical Formula = Molecular Fromula/n
322
Empirical formula is the simplest atomic ratio of atoms in a molecule. Which compound does not have empirical formula CH2O
Methanol
323
Combustion analysis is primarily used to determine:
Empirical Fromula
324
Mole of a substance can be related:
➡Avogadro's number
➡Molar Mass
➡Molar Volume
325
The mass of one mole of electron is:
0.55 mg
326
The number of carbon atoms in 45g of C6H12O6:
1.50 x NA
327
Combustion analysis cannot determine empirical formula of:
Amino acid
328
Volume of nitric oxide gas produced by the following reaction of 14g N2 with excess oxygen is:
22.4 dm^3
329
Which of the following has maximum mass:
0.5 mole of Ca
330
3NA number of ionizable H+ are present in 1 mole of:
H3PO4
331
Empirical formula of a compound CH2O with molar mass 60 g/mol belongs to which class of biochemical compound:
Carboxylic acids
332
What is the mass of CaCO3 which on heating produces 0.5 moles of CO2 gas:
50g
333
Select the suitable term about 17g of OH-:
1g ion
334
How many gram atoms in 0.1 kg of calcium:
2.5
335
Which statement is incorrect about Helium:
He exist as diatomic molecule only
336
A sample of liquid consisting of carbon, hydrogen, and oxygen was subjected to combustion analysis, 24g of compound gave 22g of CO2. What is % age of carbon
25%
337
1 gram atom of carbon is present in one mole of which of the following specie/substance.
CaCo3
338
When 2g H gas and 16g O2 gas react completely to produce H2O.What is non-limiting reactant.
Both are consumed completely
339
A man drinks 250cm3 water in a glass containing 18g glucose the minimum number of atoms received by him are of:
Carbon
340
Determine the number o moles of H-atoms in 18g of C6H12O6:
0.6 mole
341
Which is a macromolecule:
Haemoglobin
342
The moelcular mass of D2O is:
(D2O is heavy water)
20.03
343
Total number o oxygen atoms are present in 44g of N2O:
1 NA
344
One mole of an organic compound is completely burnt in excess of oxygen which compound exactly five moles of water:
Butanol
345
The molar mass of compound is 180g/mol with 40%, 6.67%, 53.3% of C, H and oxygen respectively calculated from combustion analysis. Empirical formula of this compound is:
CH2O
346
Number of grams of NaOH required for complete neutralization of 1 mole of H2SO4 on its complete ionization:
80g
347
H2O, HF and Na+ have same:;
Number of electrons
348
Number o molecules in 1.8g of glucose:
6.02 x 10^21
349
How many chlorine atoms are in 2 moles of Cl:
2 x 6.02 x 10^23
350
The statement which is incorrect about stoichiometric calculation:
Reactions may be reversible
351
The formula which shows the simplest whole number ration for the atoms of different elements in a compound:
Empirical Formula
352
The amount of product calcualted from the balanced chemical equation represent:
Theoretical Yield
353
In combustion analysis, H2O abosrber contain:
Mg(ClO4)2
354
1.5 x 10^23 molecules of O3 at STP has mass;
12g
355
Mass of Al in 51g of Al2O3:
27g
356
Mass of one magnesium atom is;
➡3.98 x 10^-23g
➡24g/NA
➡24amu
357
21g of lime is produced if 50g of lime stone is roasted. What is % yield.
75%
358
A balanced chemical equation tells us about the;
Quantitative relationship between reactants and products
359
2.8g of unknown gas occupies a volume of 2.24 dm3 at STP unknown gas is:
CO
360
Which is correct statement about limiting reactant:
➡It is concept of stoichiometry
➡It is taken in less amount than stoichiometric amount
➡Control amount of product
361
Relationship between empirical and molecular form is M.F = n(E.F). For which compound value of n=1:
C12H22O11
362
Mole of SO3 if it contains 16g of oxygen:
1/3
363
How many moles of of NH3 are produced on reacting 3 moles of N2 with 10 moles of H2:
6 moles
364
A compound has an empirical formula CH2O and molecular formula mass as 90g/mol, Identify the compound:
C3H6O3
365
What is volume occupied by 2.2g of N2O at STP:
1120.7 cm^3
366
5.6 dm3 of oxygen gas is collected at STP from Hydrilla plant by photosynthesis. The mass of oxygen produced is:
8g
367
The compound which cannot be analyzed by combustion analysis:
Urea
368
9.8g of sulphuric acid has mass of sulphate ions:
9.6g
369
9g of ice has number of covalent bonts:
6.02 x 10^23
370
A well known ideal gas is enclosed in a container having volume 5603cm3 at STP. Its mass comes out to be 16g. The unknwon gas is:
CO2
371
The efficiency of a chemical reaction can be checked by calculating:
Amount of product ormed
372
Identify the type of yield that can be obtained thorugh experiment:
Actual Yield
373
If 24g of organic compound is burnt in combustion tube which gives 22g of CO2. %age of carbon is:
25%
374
Which of the following term is correct for H=1.008 amu
➡Relative atomic mass
➡Average atomic mass
➡Fractional atomic mass
375
7g of CaO is produced if 50g of CaCO3 is roasted. Find %age yield.
25%
376
Under standard conditions, stoichiometry can be applied to:
2H2O➡2H2 + O2
377
Identify the correct statement about acetic acid and oxalic acid
Both have differnet empirical formula
378
5g of C and 10g of Mg contain equal number of:
Atoms
379
Volume occupied by 114g of F2 at STP is:
67 dm3
380
Which of the following sub-shell does not exist:
3f
381
An electron in a hydrogen atom makes
a transition from an energy level E1 to one with energy E2 and simulatenously emits a photon. The wavelength of the emitted photon is:
hc/E2 -E1
382
Identify the element that have same number of s and p electrons:
Mg
383
Energy emitted or absorbed by a body in the form of quanta. This is:
Planck's Quantum Theory
384
Unit of Planck's constant is:
J/m
385
The third electron of L atom will have quantum number values;
➡n=2
➡l=0
➡m=0
➡s=+1/2
386
For a given value of azimuthal quantum number l, the total number of values for magnetic quantum number 'm' are given by:
2l -1
387
The magnetic quantum number for the valence electron of K(Z=19) is:
Zero
388
Quantum number which describe shape of orbitals:
Magnetic quantum number
389
Number of electrons in chloride on:
18
390
With the increase in value of principal quantum number which one will not change:
Shape of p-orbitals
391
Which one orbital is bilobed with collar:
dz2
392
A covalent compound of simplest formula CH has molar mass of 78g/mol. Its molecular formula will be:
6 times of its empirical formula
393
H2 burns in Cl2 to produce HCl. The ratio of masses of reactants in chemcial reaction:
H2 + Cl2 ➡2HCl
1:35.5
394
Which of the following has same number of molecules as present in 11g of CO2:
4.5g of H2O
395
1 mole of CH3OH and 1 mole of C2H5Oh have equal number of:
O-atoms
396
Which one will produce largest number of negatively charged ions in case of 100% ionization o f1mole of:
AlCl3
397
A compound has 50% of A (molecular mass=20g/mol) and 50% of B (molecular mass=10g/mol). Empirical formula is:
AB2
398
1 mole of each N2O and CO2 has same number of:
➡Molecules
➡Atoms
➡Electrons
399
Atomic mass unit is:
1/12th of mass of one C-atom
400
The number o atoms present in 0.1 mole of oxygen gas are:
2 x 6.02 x 10^22
401
The maximum amount of the product that can be prodcued by a given amount of a reactant, according to balanced chemical equation is called:
Theoretical Yield
402
Which of the following compounds does not show same molecular and empirical ormula:
(CHO)2
403
The number of oxygen atoms in 44g of CO2 is:
2NA
404
Number of electrons in 1.8g of steam.
NA
405
1 gram moelcule of methane has mass of:
16g
406
Avogadro's number o atoms are present in:
3.2g CH4
407
The number of molecules in 11g of N2O is:
1.505 x 10^23
408
1 amu is equal to:
1.661 x 10^-21 mg
409
In combustion analysis, H2O vapours absorption is an example of:
Neutralization Reaction
410
14g of a gas contains 3.01 x 10^23 molecules at STP. The gas is:
N2
411
Which type of relationship can be studied with the help of balanced chemical equation:
➡Mass-Volume
➡Mole-Mole
➡Mole-Volume
412
The mass of an atom compared with mass of one atom of C-12 is called:
Relative atomic mass
413
58.5 amu is ____ of Rock salt.
Relative Formula Mass
414
All reactants are converted to product and no side reaction takes place are basic assumption while doing calculations for:
➡Limiting Reactant
➡Theoretical Yield
➡Stoichiometry
415
18g of water is produced if 2g of hydrogen react with ___ of oxygen.
16g
416
Avogadro's number represents the number of:
Atoms in 24g of Mg
417
Which one of the following terms is not used for ionic compounds?
Molecular ormula
418
98g H2SO4 contains number of moles of ions:
3.0 moles of ions
419
Cationic molecualr ions are produced by:
➡α-rays
➡Beam of electrons
420
Isotopes differ in:
Properties which depend upon mass
421
Which one of the following mathematical relationships is correct for (m/e) in connection with Dempster's mass spectrometer?
m/e = H2r2/2E
422
Symbol indicates not only the name of elements but also represents all of the following EXCEPT:
1 amu
423
Which of the following is not mono-isotopic element?
Cl
424
Which of the following statements is incorrect?
Number of cationic molecular ions is less than number of anionic molecular ions
425
What volume of oxygen gas is required for the complete combustion of 5cm3 of ethyne (C2H2)?
12.5 cm#
426
The relative atomic mass of boron, which consists of isotope of Boron-10 and Boron-11 is 10.8 amu. What is the percentage of Boron-10 atoms in the isotopic mixture.
20%
427
How many carbon atoms are present in 34.2g of sucrose.
(Molecular Mass of Sucrose=342)
7.2 x 10^23
428
What is the number of molecules in 1000cm^3 of nitrogen gas under room conditons.
2.5 x 10^22
429
Which is the correct sequence of stages in mass spectrometer?
Ionization , Separation, Detection, Amplification, Recording
430
How many total number of atoms are present in 49.0g of sulhpuric acid:
7 x 3 x 10^23
431
An organic compound has empirical formula CH2O. If molar mass of the compound is 90grams, then molecular formula of this organic compound would be:
C3H6O3
432
How many bromine atoms are in 3 moels of bromine element?
3 x 6.022 x 10^23 atoms
433
Carbon dioxide gas produced during combustion analysis of given organic compound is abosrbed in 50% of KOH solution. It is a:
Chemical Change only
434
In the experimental determination of the percentage of carbon and hydrogen in an organic compound, water absorbed by:
Mg(ClO4)2
435
12g of magnesium (Mg) reacts with dilute sulphuric acid to produce hydrogen gas. The amount of hydrogen gas produced is:
1g
436
Identify the correct statement about yield.
Experimental error does not affect actual yield
437
A solution contains three components A, B and C in the molar ratio 3:6:1. The percentage of mole fraction of component A is:
30%
438
Isotopes of an element have all of the following different properties EXCEPT:
They have diferent chemical properties
439
The combustion analysis of an organic compound shows
60% carbon, 8% hydrogen and 32% oxygen. If the
molecular mass of the given organic compound is 200,
then the molecular formula of the organic compound is
(Ar of C = 12 amu, H = 1 amu and O = 16 amu):
C10H16O4
440
Ascorbic acid (vitamin C) contains 48% carbon, 4% hydrogen and 48% oxygen. Which of the following iempirical formula of ascorbic acid?
C4H4O3
441
The number of moles of sodium hydroxide present in 2.5dm3 of 0.5M aqueous solution is:
1.25
442
Calcium reacts with excess oxygen to form calcium oxide (CaO) as shown in the equation:
2Ca + O➡2CaO2
The maximum mass of CaO formed when 4.0g of calcium
is burnt in excess oxygen (Ar values Ca = 40amu, O = 16amu):
5..6 g
443
If we know the mass of one substance, we can calculate the volume of other substance and vice versa with the help of a balanced chemical equation, which is called:
Mass-Volume Relationship
444
By using the value of Avogadro's number. Calcualte the total number of atoms in 7.1g of Cl-element.
1.2 x 10^23 Cl-atoms
445
Whoch one of the following has same number of moelcules as present in 11g of CO2?
4.5 g of H2O
446
28g of N2 gas at STP will occupy the volume of:
22.414 dm^3
447
Which of the following statements about 12g sample of C-12 is incorrect?
The number of C-atoms is the same as electrons in 16 g of S
448
Isotopes of an element possess:
Same chemical but different physical properties
449
When lime stone is roasted, quick lime is produced. The actual yield of CaO is 0.5 kg when 1kg of limestone is roasted. What is the percentage yield of this reaction?
CaCO3 ➡CaO + CO2
89.3%
450
Which of the following statement is correct:
The properties of an element mostly corresponded to the most abundant isotope of that element
451
A sample in the ionization chamber o mass spectrometer is ionized by:
Electrons
452
One mole of CO2 contains:
➡22-Moles Electrons
➡6.022 x 10^23
453
Total number of atoms present in 49.0g H2SO4 are:
7 x 3.011 x 10^23 number of atom
454
Mass spectrum is obtained by plotting graph between:
m/e along x-axis and relative number of ions along y-axis
455
The number of moles of CO2 which contains 16g of oxygen is:
0.5
456
Which one of the following is not generally same for one mole of different gases at STP?
Molecualr Mass
457
4g H2 reacts with 32.0g O2 to produce water. Which of the following statements is correct?
2.0 mole water is produced
458
Which of the following is correct sequence of processes involved in modern mass spectrometer?
Vaporization, Ionization, Electric Field, Magnetic field, Ion Collector, Amplification and Recordng
459
The volume occupied by 1.6g of O2 at STP is:
1.12 dm3
460
Which of the followng is incorrect isotopes of an element?
They have different position in the modern periodic table
461
The electrometer is also called as:
Ion Collector
462
Which information obtained from electrometer gives the relative abundance o ions of a definite m/e value?
Strength of electric current
463
Thee combustion analysis of an organic compound shows 60% carbon, 8% hydrogen and 32% oxygen. If the molecualr mass of the given organic compound is 200, then the molecular formula o the organic compound is:
C10H16O44
464
Which represent the simple ratio of atoms present in a compound?
Empirical Formula
465
Which of the following contains one mole o the stated particles?
Electrons in 1g of hydrogen gas
466
Total number of atoms present in 17g of hydrogen peroxide is:
1.2 x 10^24
467
0.5 mole of magnesium is burnt in excess oxygen. How much amount of MgO is produced in this reaction
2Mg + O2 ➡2MgO
20g
468
Which one of the following is CO2 abosrber?
KOH
469
Which one of the following is not a water absorber?
➡conc. H2SO4❌
➡Anhydrous CuSO4❌
➡CaCO3✅
➡Mg(ClO4)2❌
470
Which one of the following compound doesn't have same molecular formula and empirical formula?
CH3COOH
471
For those compounds which have same moelcular and empirical formula, the value of simple multiple 'n' is?
1
472
The value of simple mutliple 'n' is:
The ratio of moelcular mass and empirical mass
473
One gram molecular mass of diferent substances expressed in grams must possess:
Some times same masses and some times different masses n them
474
One mole of different compounds has:
Diferent masses but same number of molecules
475
Which one of the following statement is not true about molecule?
Molecule always consist of more than one atoms
476
Molar volumes is 22.414 dm3 , it is true:
Only when the gas is ideal
477
One mole of an ideal room temperature and pressure occupies a volume of:
22.414 dm3
478
414 dm3 of each gas at STP has:
a different mass but the ame number of molecules
479
Many elements have fractional atomic mass. This is because:
Atomic masses are average masses of isotopes proportion to their relative abundance
480
For a reaction X +2Y➡Z. The amount of Z formed by starting the reaction with 5 moels of X and 8 moels of Y:
4 moles
481
One mole of water and one mole of methane have an equal:
Number of molecules
482
A compound has an empirical formula CH2Cl, and molecular/formula mass as 99g/mol, identify the compound
C2H4Cl2
483
The Avogadro's number is the number of:
Number o the molecules of CO2 in 44g
484
The empirical formual of a compound s CH2O. What other information is needed to determine its molecular formula?
Relative molecular mass of the compound
485
100g of CaCO3 is decomposed, the CO2 produced occupies a volume at STP
22.414 dm3
486
Methanol burns with oxygen. If 1 mole of methanol is burnt in oxygen, then how many moles of water are prodcued:
2 moles
487
The number of moles of O2 produced by thermal decomposition o 245g of KClO3.
(Molar mass of KClO3 = 122.5 g/mol)
3 moels
488
The reactant left un-used after completion o reaction is knwon as:
➡Reactant in excess
➡Non-Limiting Reactant
489
The quantity of a product that is actually produced in a chemical reaction is called:
Actual Yield
490
50g limestone is heated to give 14g CaO in a chemical reaction. What will be the % yield of this reaction
50%
491
8g of gas "X" occupies 11.207 dm3 volume at STP. The gas "X" will be:
CH4
492
Mass of water in 100 moels o ice is:
1.8 kg
493
The realtive atomic mass of chlorine is 35.5 amu. What is the mass of 2 mole of chlorine gas:
142g
494
The Na2CO3 has 106 g. This is called its:
Formula Mass
495
The volume occupied by 4.4g of CO2 gas at STP is:
2.24 dm3
496
Complete oxidation o one mole of an organic compound requires three mole of oxygen gas. The formula of the organic compound will be:
CH3CH2Oh
497
A limiting reactant is the one which:
Gives the minimum amount of product
498
Which statement is incorrect:
One gram atom of sodium is equal to one gram sodium
499
Combustion analysis is used to determine the _____ of an organic compound:
Empirical Formula
500
23g of sodium and 24g of magnesium have equal ____ in them.
Number of atoms
501
720g of glucose contains how many moles of glucose.
4
502
An unknown compound has empirical formula CH3O. Its molar mass is 62g/mole. The compound may be:
CH2(OH)CH2(OH)
503
Quantitative relations between reactants and products in a balanced chemical equation is known as:
Stoichiometry
504
32g mof methanol contains:
➡1g-atom of "C"
➡4g-atom of "H"
➡1g-atom of "O"
505
The efficiency of a chemical reaction can be determined with the help of:
%age Yield
506
What is the mass of 2.5 moles of Al2O3
255g
507
58.5 amu mass of NaCl called as:
Formula Mass
508
When 0.5 mole of NaCl is dissolved in water, it produces Na+ ions equal to:
3.01 x 10^23
509
NH3 is an important raw material in the manufacture of fertilizers. It is obtained by the combination o N2 and H2. How many moles of N2 are required to manufacture 3 moles of NH3.
1.5 moles
510
How many moles of oxygen moelcuels are there n 89.656dm3 of oxygen gas at STP
4 moles
511
How many number of moles of hydrogen atoms are present in 36g H2O:
1 mole
512
The actual yield may be less than the theoretical yield due which of the following reason:
➡Side reactions may produce by-products
➡Some reactions are reversible
➡Mechanical loss takes palce due to filtration and distillation
513
Which of the following terms is used for 18g H2O?
g- molecule
514
A piece of diamond embedded in a gold ring weighs 6000mg. How many number of
moles of carbon does it contain?
0.5 mole
515
ne mole of helium gas can occupy 22.414 dm3 volume at
298K and one atm pressure
516
Number of water molecules in 9g of ice.
3.01 x 10^23
517
Number of moles of NO2 which contains 16g oxygen is:
0.50 mole
518
A balanced chemical equation tells us about:
Quantitative relationship between reactants and products
519
Which is true about acetic acid and oxalic acid?
Diferent empirical formula
520
CH2O is tge empirical ormula of:
➡Acetic acid
➡Glucose
➡Lactic acid
521
Which of the following terms is used for 238g of uranium:
1g atom
522
Total number o electrons present in 34g of OH- are:
20Na
523
The number of molecules in one mole atom of a substance.
NA of atoms
524
For stoichiometry calculations ,we have to assume:
All the reactants are completely converted into products
525
What wll be volume of 1.5 moels of chlorine molecules occupy at STP.
33.6 m3
526
2.5 mole of H2 and 2.5 mole of O2 at same temperature and presure have equal:
➡Volume
➡Molecules
➡Atoms
527
While finding the relative atomic mass, which of the following standard is used to compare the atomic mass of chlorine
Carbon-12
528
One mole o ethanol and one mole of ethane have equal:
Number o molecules
529
The amount o product obtained without perfforming an experiment is knwon as:
Theoretical Yield
530
1 amu is equal to:
1.661 x 10^-27 kg
531
An organic compound has empirical formula C3H3O if molar mass of the compound
is 110.15 molecular formula of this organic compound is:
C6H6O2
532
The number of molecules in 44.5 g of ice is:
1.5 x 10^23
533
The formula which shows the simplest whole number ratio for the atoms of different
elements in compound
Empirical Formula
534
Number o covalent bonds in 1.7g of NH3:
1.8 x 10^23
535
11.2 dm3 of an ideal gas at STP weighs 15g predict the gas.
NO
