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Chemistry
Mole Concept
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1
A
B
C
D
2
A
A mole of an element
B
A mole of a compound
C
An atom of an element
D
An atom of a compound
3
One mole of which species has maximum number of electrons?
A
B
C
D
4
Scientific notation for the number 0.0001345 is
A
1.345 × 10⁻⁴
B
1.345 × 10⁻⁵
C
1.345 × 10⁻³
D
1.345 × 10⁻⁶
5
A
B
C
D
6
A
Both correct
B
I correct II incorrect
C
I incorrect II correct
D
Both incorrect
7
Number of atoms present in 16 amu of He is;
A
4 NA
B
NA/4
C
4
D
8
8
A
B
C
D
9
Given below are two statements: Statement-I: 1 mole H2SO4 contains same mass of oxygen and sulphur. Statement-II: 1 mole H2SO4 represents 98 g mass.
A
Statement I is correct but Statement II is incorrect.
B
Statement I is incorrect but Statement II is correct.
C
Both Statement I and Statement II are correct.
D
Both Statement I and Statement II are incorrect.
10
Given below are two statements: Statement-I: Average atomic mass of chlorine is fractional. Statement-II: Average atomic mass is calculated by using natural abundances of different isotopes.
A
Statement I is correct but Statement II is incorrect.
B
Statement I is incorrect but Statement II is correct.
C
Both Statement I and Statement II are correct.
D
Both Statement I and Statement II are incorrect.
11
A mixture of gases contains H2 and O2 gases in the ratio of 1 : 4 (w/w). What is the molar ratio of two gases in the mixture?
A
1 : 2
B
4 : 1
C
2 : 2
D
2 : 3
12
A
Statement I is correct but Statement II is incorrect.
B
Statement I is incorrect but Statement II is correct.
C
Both Statement I and Statement II are correct.
D
Both Statement I and Statement II are incorrect.
13
Given below are two statements: Statement-I: Atoms are neither created nor destroyed in a chemical reaction. Statement-II: Compounds are formed when atoms of different elements combine in a fixed ratio.
A
Statement I is correct but Statement II is incorrect.
B
Statement I is incorrect but Statement II is correct.
C
Both Statement I and Statement II are correct.
D
Both Statement I and Statement II are incorrect.
14
1 amu is equal to:
A
B
C
D
15
A
75%, 25%
B
25%, 75%
C
85%, 15%
D
15%, 85%
16
What is the mass of oxygen required for the complete combustion of 2.8 kg of ethylene? C2H4 + 3O2 → 2CO2 + 2H2O
A
2.8 kg
B
6.4 kg
C
9.6 kg
D
6.9 kg
17
A
B
C
D
18
If isotopic distribution of ¹²C and ¹⁴C is 98.0% and 2.0%, respectively, then the number of ¹⁴C atoms in 12 g of carbon is:
A
B
C
D
19
A
5
B
2.5
C
1
D
0.5
20
The correct scientific notation for 0.0000212 is:
A
B
C
D
21
80 g of oxygen gas contains as many atoms as in;
A
10 g of hydrogen gas
B
5 g of hydrogen gas
C
80 g of hydrogen gas
D
1 g of hydrogen gas
22
How many significant figures are in 0.0005?
A
1
B
2
C
3
D
4
23
A
B
C
D
24
A
17 g
B
C
D
25
A
Both correct
B
I correct II incorrect
C
I incorrect II correct
D
Both incorrect
26
One atomic mass unit is defined as a mass exactly equal to:
A
B
C
D
27
A
8 : 16 : 1
B
16 : 8 : 1
C
16 : 1 : 2
D
8 : 1 : 2
28
The ratio of total number of electrons present in 48 g of O₃ to 24 g of O₂ is
A
1 : 3
B
2 : 3
C
3 : 2
D
2 : 1
29
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion (A): One amu is equal to 1.66 × 10⁻²⁷ kg. Reason (R): One amu is the actual mass of one atom of C–12.
A
A is true but R is false.
B
A is false but R is true.
C
Both A and R are true and R is the correct explanation of A.
D
Both A and R are true but R is NOT the correct explanation of A.
30
The number of water molecules is maximum in
A
1.8 moles of water
B
1.8 g of water
C
18 g of water
D
18 moles of water
31
Compounds A, B and C have same empirical formula CH3. If molecular formula of compound – A, B and C is x, y and z respectively then select correct statements. A. x may be (CH3)2 B. z may be (CH3)1.5 C. y may be (CH3)5
A
A and B only
B
Only C only
C
C and B only
D
A and C only
32
A
100 mL
B
80 mL
C
40 mL
D
200 mL
33
How many moles of electron weigh one kilogram?
A
6.022 × 10^23
B
(1 × 10^31)/9.1
C
(6.022 × 10^54)/9.1
D
(1 × 10^8)/(9.1 × 6.022)
34
Formula mass is used instead of molecular mass for:
A
B
NaCl
C
Ne
D
35
A
B
C
D
36
A
7.5 g
B
6.3 g
C
4.9 g
D
8.8 g
37
Which of the following concentration term is temperature dependent?
A
Mole fraction
B
Weight percentage
C
Molality
D
Molarity
38
A
B
C
D
39
Given below are two statements: Statement-I: Avogadro’s number is a dimensionless quantity. Statement-II: Avogadro’s number is equal to the number of atoms or molecules in one gram mole.
A
Statement-I and Statement-II both are correct.
B
Statement-I is correct but Statement-II is incorrect.
C
Statement-I is incorrect but Statement-II is correct.
D
Statement-I and Statement-II both are incorrect.
40
A
B
C
D
41
The volumes of hydrogen & oxygen when combined to form H2O bear a simple ratio of 2:1. This is explained by;
A
Law of Multiple Proportions
B
Avogadro’s Law
C
Law of Definite Proportion
D
Gay Lussac’s Law of Gaseous Volumes
42
A
B
C
D
43
With increase of temperature, which of these changes?
A
Molality
B
Weight fraction of solute
C
Molarity
D
Mole fraction
44
Avogadro’s number is the number of molecules present in
A
1 g of molecule
B
1 atom of molecule
C
gram molecular mass
D
1 Litre of molecule
45
Empirical formula of a hydrocarbon containing 85.71% carbon is:
A
CH
B
C
D
46
A
14 g of N₂ + 4 g of H₂
B
28 g of N₂ + 7 g of H₂
C
56 g of N₂ + 10 g of H₂
D
47
Find the number of atoms present in 1.6 g of methane:
A
B
C
D
48
A
B
C
D
49
The statement which correctly represents Avogadro’s hypothesis is:
A
B
C
D
50
A
B
C
D
51
A
B
C
D
52
A
0.1 mole
B
0.2 mole
C
0.05 mole
D
0.5 mole
53
A
B
C
D
54
The number of significant figures for the three measurements 161 cm, 0.161 cm, 0.0161 cm are respectively
A
3, 4 and 5
B
3, 4 and 4
C
3, 3 and 4
D
3, 3 and 3
55
The number of atoms in 0.1 mole of a triatomic gas is;
A
6.026 × 10^22
B
1.807 × 10^23
C
3.600 × 10^23
D
1.800 × 10^22
56
Given below are two statements: Statement-I: 1g O2 and 1g O3 have equal number of atoms. Statement-II: Mass of 1 mole of an atom is equal to its gram-atomic mass.
A
Statement I is correct but Statement II is incorrect.
B
Statement I is incorrect but Statement II is correct.
C
Both Statement I and Statement II are correct.
D
Both Statement I and Statement II are incorrect.
57
A measured temperature on Fahrenheit scale is 200°F. What will this reading be on the Celsius scale?
A
40°
B
91.5°
C
93.3°
D
30°
58
A
B
C
D
59
A
B
C
D
60
Which of the following alkanes has 75% of carbon?
A
B
C
D
61
A molal solution is the one that contains one mole of a solute in:
A
1000 g of the solvent
B
one litre of the solvent
C
one litre of the solution
D
100 g of the solvent
62
The prefix for multiple 10⁻¹² is;
A
giga
B
pico
C
kilo
D
mega
63
20 g of metal combines with oxygen to form 60 g of metal oxide (MO). The percentage of oxygen in metal oxide is:
A
84.3%
B
72.9%
C
33.3%
D
66.6%
64
A
34.25%
B
52.17%
C
73.71%
D
46.26%
65
One gram molecule of benzene is equal to;
A
10 g C6H6
B
70 g C6H6
C
72 g C6H6
D
78 g C6H6
66
A
B
CHO
C
D
67
An element, X has the following isotopic composition: 200X:90%, 199X:8.0%, 202X:2.0% The weighted average atomic mass of the naturally occurring element X is closest to
A
201 u
B
202 u
C
199 u
D
199.96 u
68
The maximum number of atoms are present in:
A
B
C
16 g of atomic oxygen
D
69
A
Avogadro
B
Definite proportions
C
Multiple proportions
D
Gay-Lussac
70
A
B
C
D
71
A
A-IV, B-I, C-II, D-III
B
A-I, B-IV, C-III, D-II
C
A-III, B-I, C-II, D-IV
D
A-IV, B-III, C-I, D-II
72
The value of 40°C in Fahrenheit scale will be:
A
40°F
B
98°F
C
100°F
D
104°F
73
A
2.4 g
B
1.5 g
C
3 g
D
4.5 g
74
A
B
C
D
75
A
B
C
D
76
A
56%
B
76%
C
68%
D
63%
77
Formation of CO and CO2 illustrates the law of ;
A
Law of conservation of mass
B
Avogadro’s law
C
Law of Constant Proportion
D
Law of Multiple Proportion
78
5.85 g NaCl is dissolved in 1 L water. The total number of Na+ and Cl– ions in 1 mL of this solution will be;
A
6.02 × 10^19
B
1.2 × 10^22
C
1.2 × 10^20
D
6.02 × 10^20
79
Number of moles present in 3.6 g of a gas having vapour density 18 is:
A
0.02
B
0.1
C
0.2
D
0.01
80
A solution contains 4 mol of ethanol and 6 mol of water. The mole fraction of ethanol in the solution is;
A
0.6
B
0.2
C
0.8
D
0.4
81
Match List-I with List-II A. 3 mole of Fe3S2 B. 1 mole of FeSO4 C. 2 mole of O3 D. 1.5 mole of K2CO3
A
A-I, B-II, C-III, D-IV
B
A-II, B-III, C-I, D-IV
C
A-III, B-IV, C-II, D-I
D
A-IV, B-II, C-III, D-I
82
A
B
C
D
83
A
B
C
D
84
A quantity of 2.0 g of a triatomic gaseous element was found to occupy a volume of 448 ml at 76 cm of Hg and 273 K. The mass of its each atom is:
A
100 amu
B
C
33.3 g
D
5.53 amu
85
A
66.6%
B
70%
C
10%
D
50%
86
The law of multiple proportions is illustrated by the pair of compounds;
A
NaCl and NaBr
B
H2O and D2O
C
SO2 and SO3
D
Mg(OH)2 and MgO
87
A
B
C
D
88
A
0.1 M
B
0.01 M
C
1 M
D
10 M
89
A
B
C
D
90
A
2 mol
B
2.5 mol
C
1.5 mol
D
4 mol
91
The simplest formula of the compound containing 50% X (atomic mass 10 amu) and 50% Y (atomic mass 20 amu) is;
A
B
C
D
92
The maximum amount of BaSO4 that can be obtained on mixing 0.5 mol BaCl2 with 1 mol H2SO4 is
A
0.5 mol
B
0.1 mol
C
0.15 mol
D
0.2 mol
93
A
0.477 M and 0.477 M
B
0.955 M and 1.910 M
C
1.910 M and 0.955 M
D
1.90 M and 1.910 M
94
What are the multiples for pico and deci respectively?
A
B
C
D
95
A
B
C
D
96
A
B
C
D
97
A
B
C
D
98
For which of the following reactions Gay-Lussac’s law is not valid?
A
B
C
D
99
Which of the following is an example of a compound?
A
Sugar solution
B
Hydrogen
C
Ammonia
D
Sodium
100
8 g NaOH is dissolved in one litre of solution, its molarity is:
A
0.8 M
B
0.4 M
C
0.2 M
D
0.1 M
101
Consider the following statements. A. 1 mole electrons are equal to 6.022 × 10^23 electrons. B. The mass of NA electrons is equal to 5.48 × 10^−7 kg C. Number of particle present in 1 mole of nitrogen atom are 6.023
A
Only A
B
Only C
C
Only B
D
A, B and C
102
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion (A): Molality and mole fraction concentration units do not change with temperature. Reason (R): The concentration terms, molality and mole fraction do not involve volume terms.
A
A is true but R is false.
B
A is false but R is true.
C
Both A and R are true and R is the correct explanation of A.
D
Both A and R are true but R is NOT the correct explanation of A.
103
A
B
C
D
104
A
B
C
D
105
A
38.4 %
B
46.6 %
C
59.1 %
D
61.3 %
106
A
16 g
B
16 mg
C
16 u
D
107
How many molecules does 1 mole of carbon dioxide contain?
A
2NA
B
5NA
C
3NA
D
NA