220 Books Doubtnut Question Bank

CHEMISTRY
BOOKS - MTG CHEMISTRY (ENGLISH)
SOME BASIC CONCEPTS OF CHEMISTRY
Mcq
1. Few quantities with their units are listed below. Mark the
units which are not correctly matched.
(i) Density : kg m −3
(ii) Velocity of light : m s −1
(iii) Planck's constant : J −1

s
−1
(iv) Acceleration : ms −2
A. (ii) and (iv)
B. (i) and (iii)
C. (iii) and (v)
D. (iv) and (v)
Answer:
Watch Video Solution
2. Mark the conversion factor which is not correct.
A. 1 atm = 1.01325 × 10
5
pa
B. 1 metre = 39.37 inches
C. 1 litre = 10
−3
m
3
D. 1 inch =3.33 cm
Answer:
3. Few figures are expressed in scientific notation. Mark the
incorrect one.
A. 234000 = 2.34 × 10
5
B. 8008 3
= 8 × 10
C. 0.0048 = 4.8 × 10
−3
D. 500.0 = 5.00 × 10
2
Answer:

4. Markthe rule which is not correctly stated about
determination of significant figures.
A. Zeros preceding to first non-zero digit are not
significant.
B. Zero between two non-zero digits are not significant.
C. Zero at the end or right of the number are significant if
they are on the right side of decimal point.
D. All non - zero digits are significant.
Answer: B

5. Which of the following rules regarding the significant
figures and calculations involving them is not correct?
A. The result of an addition or subtraction is reported to
the same number of decimal places as present in
number with least decimal places.
B. Result of multiplication or division should have same
number of significant figures as present in most
precise figure.
C. The result of multiplication or division should be
rounded off to same number of significant figures as
present in least precise figure.

D. The non-significant figures in the measurements are
rounded off.
Answer:
6. The result of the operation 2.5 × 1.25 should be which of
the following on the basis of significant figures?
A. 3.125
B. 3.13
C. 3.1
D. 31.25
Answer:
7. How many significant figures are present in 0.010100 × 10

3
A. 7
B. 5
C. 3
D. 10
Answer: B

8. What will be the answer in appropriate significant figures
as a result of addition of 3.0223 and 5.041 ?
A. 80.633
B. 8.0633
C. 8.063
D. 806.33
Answer:
9. Which of the following is the most accurate measurement?
A. 9m
B. 9.0m
C. 9.00m
D. 9.000m
Answer:
10. Which of the following option is not correct ?
A. 2.300+0.02017+0.02015=2.340
B. 126, 000 has 3 significant figures.
C. 15.15μs = 1.515 × 10
−5
s
D. 0.0048 = 48 × 10
−3
Answer:
11. What should be the volume of the milk (in m

3
) which
measures 5L?
A. 5 × 10 −3
m
3
B. 5 × 10
3
m
3
C. 5 × 1000m 3
D. 5 × 10
6
m
3
Answer:

12. How many seconds are there in 3 days?
A. 259200 s
B. 172800 s
C. 24800 s
D. 72000 s
Answer:
13. 18.72 g of a substance 'X' occupies 1.81 cm

3
. What will be
its density measured in correct significant figures?
A. 10.3gcm −3
B. 10.34gcm −3
C. 10.4gcm −3
D. 10.3425gcm −3
Answer:
14. 4.88 g of KClO when heated produced 1.92 g of O and

3 2
2.96 g of KCl. Which of the following statements regarding
the experiment is correct?
A. The result illustrates the law of conservation of mass.
B. The result of illustrates the law of multiple
proportions.
C. The result illustrates the law of constant proportion.
D. None of the above laws is followed.
Answer:
15. How much mass of silver nitrates will react with 5.85 g of
sodium chloride to produce 14.35 g of silver chloride and 8.5
g of sodium nitrates if law of conservation of mass is
followed?
A. 22.85 g
B. 108 g
C. 17.0 g
D. 28.70 g
Answer: C
16. What mass of hydrochloric acid is needed to decompose
50 g of limestone?
A. 36.5 g
B. 73 g
C. 50 g
D. 100 g
Answer: A
17. What mass of sodium chloride would be decomposed by
9.8 g of sulphuric acid if 12 g of sodium bisulphate and 2.75 g
of hydrogen chloride were produced in a reaction?
A. 14.75 g
B. 3.8 g
C. 4.95 g
D. 2.2 g
Answer: C

18. In an experiment 2.4g of iron oxide in reduction with
hydrogen gave 1.68 g of iron. In another experimet, 2.7 g of
iron oxide gave 1.89 g of iron on reduction. Which law is
illustrated from the above data?
A. Law of constant proportions
B. Law of multiple proportions
C. Law of reciprocal proportions
D. Law of conservation proportions
Answer:

19. Which of the following statements indicates that law of
multiple proportion is being followed?
A. An element forms two oxides, XO and XO2 containing
50% and 60% oxygen respectively. The ratio of masses
of oxygen which combines with 1 g of element is 2 : 3.
B. Hydrogen sulphide contains 5.89% hydrogen, water
contains 11.1% hydrogen and sulphur dioxyde contains
50% oxygen.
C. 3.47 g of BaCl2 reacts with 2.36g of N a2 SO4 to give
3.88 of BaSO and 1.95 g of NaCl.

4
D. 20mL of ammonia gives 10 volumes of N2 and 30
volumes of H at constant temperature and pressure.

2
Answer:
20. Give below are few statements. Mark the statement which
is not correct.
A. Atoms are neigther created nor destroyed in a
chemical reaction.
B. Law of definite proportion state that a given
compound always contains exactly the same
proportion of elements by weight.
C. Gay Lussac's law of chemical combination is valid for all
substances.
D. A pure compund has always a fixed proportion of
masses of its constituents.
Answer:
21. Are the atomic masses of some elements actually
fractional ?
A. They exist as a mixture of isotopes of different masses
B. They contain impurities of other atoms
C. They are mixtures of isobars
D. They cannot be weighted accurately.

Answer: A
22. Oxygen occurs in nature as a mixture of isotopes
16
O,
17
O and
18
O having masses of 15.995 u, 16.999 u and
17.999 u and relative abundance of 99.763%, 0.037% and
0.200% respectively. What is the average atomic mass of
oxygen?
A. 15.999 u
B. 16.999 u
C. 17.999 u
D. 18.999 u
Answer: A
23. For every one 37

Cl isotopes there are three 35
Cl isotopes
in a sample of chlorine. What will be the average atomic
mass of chlorine?
A. 35
B. 37
C. 35.5
D. 35.6
Answer:

24. Carbon occur in nature as a mixture of C − 12 and
C − 13 . Average atomic mass of carbon is 12.011 what is the
% abundance of C − 12 in nature ?
A. 0.889
B. 0.989
C. 0.899
D. 0.799
Answer:

25. What is the mass of carbon dioxide which contains the
same number of molecules as are contained in 40 g of
oxygen?
A. 40g
B. 55g
C. 32g
D. 44g
Answer: B
26. The number of oxygen atoms present in 1 mole of oxalic
acids dihydrate is
A. 6 × 10 23
B. 6.022 × 10 34
C. 7.22 × 10 23
D. 36.13 × 10 23
Answer: D
27. The measured density at NT P of He is 0.1784gL

−1
.
Calculate the weight of 1mole of H e.
A. 3.99 g
B. 22.4 g
C. 3.56 g
D. 29 g
Answer:
28. Which of the following gases will have least volume if 10g
of each gas is taken at same temperature and pressure?
A. CO 2
B. N2
C. CH 4
D. HCl
Answer:
29. How many number of molecules and atoms respectively
are presetn in 2.8 liters of a diatomics gas at STP ?
A. 6.023 × 10 23
B. 6.023 × 10 23
C. 7.5 × 10 22 22
, 15 × 10
D. 15 × 10 22
, 7.5 × 10
23
Answer:
30. Total number of atoms present in 34 g of N H is 3

A. 4 × 10 23
B. 4.8 × 10 21
C. 2 × 10 23
D. 48 × 10 23
Answer: D
31. What will be the mass of 100 atoms of hydrogen?
A. 100g
B. 1.66 × 10 − 22
g
C. 6.023 × 10 23
g
D. 100 × 6.023 × 10 23
g
Answer:
32. How many atoms in total are present in 1kg of sugar?
A. 7.92 × 10 25
atoms
B. 6 × 1023
atoms
C. 6.022 × 10 25
atoms
D. 1000 atoms
Answer:

33. 1.4 moles of phosphorus trichloride are present in a
sample. How many atoms are there in the sample?
A. 5.6
B. 34
C. 2.4 × 10 23
D. 3.372 × 10 24
Answer:
34. What will be the standard molar volume of He, if its
density is 0.1784 g/L at STP?

A. 11.2 L
B. 22.4 L
C. 5.6 L
D. 2.8 L
Answer:
35. In a mixture of gases, the volume content of a gas is
0.06% at STP. Calculate the number of molecules of the gas
in 1 L of the mixture.
A. 1.613 × 10 23
B. 6.023 × 10 23
C. 1.61 × 10
27
D. 1.61 × 10
19
Answer:
36. What will be the weight of CO having the same number of
oxygen atoms at present in 22 g of CO ?

2
A. 28g
B. 22g
C. 44g
D. 72g
Answer:
37. Calculate the number of aluminium ions present in 0.051
g of aluminium oxide.
(Hint: The mass of an ion is the same as that of an atom of
the same element. Atomic mass of Al = 27 u)
A. 6.023 × 1020
ions
B. 3 ions
C. 6.023 × 1023
ions
D. 9 ions
Answer:
38. Which of the following correctly represents 180 g of water
5 moles of water
(ii) 10 moles of water
(iii) 6.023 × 10 23
molecules of water
(iv) 6.023 × 10 24
molecules of water
A. (i) and (ii)
B. (i) and (iv)
C. (ii) and (iv)
D. (ii) and (iii)
Answer:
39. How many oxygen atoms will be present in 88 g of CO ? 2
A. 24.08 × 10 23
B. 6.023 × 10 23
C. 44 × 10 23
D. 22 × 10 24
Answer: A
40. Calculate the total number of electrons present in 1.6 g of
methane
A. 6.023 × 1023
B. 16
C. 12.04 × 1023
D. 6.023 × 1024
Answer:
41. A mixture having 2 g of hydrogen and 32 oxygen occupies
how much volume at NTP?
A. 44.8 L
B. 22.4 L
C. 11.2 L
D. 76.2 L
Answer:
42. One atom of an element weight 3.32 × 10

− 23
g. How
many number of gram atoms are in 20 kg of the element?
A. 2000
B. 20
C. 200
D. 1000
Answer:
43. How much copper is present in 50 g of CuSO 4
A. 19.90 g
B. 39.81 g
C. 63.5 g
D. 31.71 g
Answer:
44. 0.48 g of a sample of a compound containing boron and
oxygen contains 0.192 g of boron and 0.288 g of oxygen.

What will be the percentage composition of the compound?
A. 60% and 40% B and O respectively
B. 40% and 60% B and O respectively
C. 30% and 70% B and O respectively
D. 70% and 30% B and O respectively
Answer: B
45. A compound of magnesium contains 21.9% magnesium,
27.8% phosphorus and 50.3% oxygen. What will be the
simplest formula of the compound?
A. M g
2
P2 O7
B. M gP O 3
C. M g 2
P2 O2
D. M gP 2
O4
Answer: A
46. A compound contains two elements 'X' and 'Y' in the ratio
of 50% each. Atomic mass 'X' is 20 and 'Y' is 40. what can be
its simplest formula?
A. XY
B. X 2
Y
C. XY 2
D. X 2
Y3
Answer: B
47. The empirical formula of a compound is CH2 O2 . What
could be its molecular formula?
A. C2
H2 O 2
B. C2
H2 O 4
C. C2
H4 O 4
D. CH 4
O4
Answer: C
48. A gas has molecular formula (CH )

n
. If vapour density of
the gas is 39, what should be the formula of the compound ?
A. C3
H3
B. C4
H4
C. C2
H2
D. C6
H6
Answer:

49. Determine the molecular formula of an oxide of iron in
which the mass percent of iron and oxygen are 69.9 and ,
30.1
respectively.
A. FeO
B. F e 3
O4
C. F e 2
O3
D. F eO 2
Answer:
50. An organic compound on analysis gave C=54.2%, H=9.2%
by mass. Its empirical formula is

A. CH O 2
B. CH 2
O
C. C2
H8 O
D. C2
H4 O
Answer:
51. The relative number of mass of elements, 'X' and 'Y' in a
compound is 0.25 and 0.5. The empirical formula of
compound is
A. XY
B. X 2
Y
C. XY 2
D. X 2
Y2
Answer:
52. Two elements 'P' and 'Q' combine to form a compound.
Atomic mass of 'p' is 12 and 'Q' is 16. percentage of 'P' in the
compound is 27.3. What will be the empirical formula of the
compound ?
A. P 2
Q2
B. PQ
C. P 2
Q
D. P Q 2
Answer:
53. 1g of Mg is burnt in a closed vessel which contains
0.5gofO2
(i) Which reactants is left in excess
(ii) Find the mass of the excess reactant.
A. O is a limiting reagent and Mg is in excess by 0.25 g.

2
B. Mg is a limiting reagent and is in excess by 0.5 g.
C. O is a limiting reagent and is in excess by 0.25 g.

2
D. O is a limiting reagent and Mg is in excess by 0.75 g.

2
Answer:
54. In a reaction container, 100g of hydrogen and 100 g of
Cl2 are mixed for the formation of HCl gas. What is the
limiting reagent and how much HCl is formed in the reaction
A. H is limiting reagent and 36.5 g of HCl are formed.

2
B. Cl is limiting reagent and 102.8 g of HCl are formed.

2
C. H is limiting reagent and 142 g of HCl are formed.

2
D. Cl is limiting reagent and 73 g of HCl are formed.

2
Answer:
55. If 40g of CaCO is treated with 40g of HCl, which of the

3
reactants will acts as limiting reagent?
A. CaCO 3
B. HCl
C. Both (a) and (b)
D. None of these
Answer:

56. The weight of AgCl precipitated when a solution
containing 5.85 g of NaCl is added to a solution containing
3.4g of AgN O is
3
A. 28g
B. 9.25g
C. 2.870g
D. 58g
Answer:
57. How much oxygen is required for complete combustion of
560 g of ethene?
A. 6.4 kg
B. 1.92 Kg
C. 2.8 kg
D. 9.6 kg
Answer:
58. How many moles of oxygen gas can be produced during
electricity decomposition of 180 g of water ?
A. 2.5 moles
B. 5 moles
C. 10 moles
D. 7 moles
Answer:
59. How many grams of CaO are required to neutralise 852g
of P 4
O10 ? Draw the structure of P 4
O10 .
A. 852g
B. 1008g
C. 85g
D. 7095g
Answer:
60. What volume of dioxygen is required for complete
combustion of 2 volume of acetylene gas at NTP ?
A. 2 volumes
B. 5 volumes
C. 10 volumes
D. 4 volumes
Answer:

61. What quantity of copper(II) oxide will react 2.80litre of
hydrogen at NTP
A. 79.5 g
B. 2 g
C. 9.9 g
D. 22.4 g
Answer:
62. At NTP, 1L of O reacts with 3L of carbon monoxide. What

2
will be the volume of CO and CO after the reaction?

2
A. 1L CO , 1L CO
2
B. 2L CO , 2L CO
2
C. 1L CO , 2L CO
2
D. 2L CO , 1L CO
2
Answer:
63. Calcium carbonate decomposes on heating to give
calcium oxide and carbon dioxide. How much volume of CO 2
will be obtained by thermal decomposition of 50g CaCO ?

3
A. 1L
B. 11.2 L
C. 44 L
D. 22.4 L
Answer:
64. Chlorine gas is prepared by reaction of H2 SO4 with
M nO2 and NaCl. What volume of Cl will be produced at STP

2
if 50 g of NaCl is taken in the reaction ?
A. 1.915 L
B. 22.4 L
C. 11.2 L
D. 9.57 L
Answer:
65. HCl is produced in the stomach which can be neutralised
by M g(OH )
2
in the form of milk of magnesia. How much
M g(OH )
2
is required to neutralise one mole of stomach
acid?
A. 29.16 g
B. 34.3 g
C. 58.33 g
D. 68.66g
Answer:
66. Magnetite, F e 3
O4 , can be converted into metallic iron by
heating with carbon monoxide as represented by this
equation:
F e3 O4 (s) + CO(g) → F e(s) + CO2 (g)
The kilograms of F e 3
O4 which must be processed in this way
to obtain 5.00kg of iron, if the process is 85 % efficient is
closest to? [M : = F e = 56]
A. 8.12 kg
B. 4.14 kg
C. 6.94 kg
D. 16.8 kg
Answer:
67. What is the mass percent of oxygen in ethanol ?
A. 52.14
B. 13.13
C. 16
D. 34.78
Answer:
68. How much mass of sodium acetate is required to make
250 mL of 0.575 molar aqueous solution?

A. 11.79 g
B. 15.38 g
C. 10.81 g
D. 25.35 g
Answer:
69. A solution is prepared by adding 5g of a solute 'X' to 45 g
of solvent 'Y'. What is the mass percent of the solute 'X' ?
A. 10
B. 11.1
C. 90
D. 75
Answer:
70. A 1.50g sample of an ore containing silver was dissolved,
and all of the Ag

+
was converted to 0.125 g of Ag2 S . What
was the percentage of silver in the ore?
A. 0.216
B. 0.072
C. 0.017
D. 0.248
Answer:
71. 2.82g of glucose is dissolved in 30g of water. The mole
fraction of glucose in the solution is
A. 0.01
B. 0.99
C. 0.52
D. 1.66
Answer:

72. What volume of water is to be added to 100 cm of 0.5M
3
NaOH solution to make it 0.1 M solution?
A. 200cm 3
B. 400cm 3
C. 500cm 3
D. 100cm 3
Answer:
73. Molarity equation of a mixture of solution of same
substance is given by
A.
M1 + V1 × M2 + V2 × M3 + V3 + … = M1 + M2 + M3
B. M 1
V1 + M2 V2 + M3 V3 + …. = M (V1 + V2 + V3 )
M1 M2 M3 1 1 1
C. + + + …. = M( + + )
V1 V2 V3 V1 V2 V3
M1 M2 M3 1 1 1
D. × × + …. = M1 ( × × )
V1 V2 V3 V1 V2 V3
Answer:
74. The final molarity of a solution made by mixing 50 mL of
0.5 M HCl, 150 mL of 0.25 M HCl and water to make the
volume 250 mL is
A. 0.5 M
B. 1M
C. 0.75 M
D. 0.25 M
Answer:
75. A solution is made by dissolving 49g of H 2

SO4 in 250 mL
of water. The molarity of the solution prepared is
A. 2 M
B. 1 M
C. 4 M
D. 5 M
Answer:
76. What is the concertration of copper sulphate (in mol
L
−1
) if 80 of it is dissolved in enough water to make a final
volume of 3 L?
A. 0.0167
B. 0.167
C. 1.067
D. 10.67
Answer:

77. 4.28g of NaOH is dissolved in water and the solution is
made to 250 cc. what will be the molarity of the solution ?
A. 0.615 mol L −1
B. 0.428 mol L −1
C. 0.99 mol L −1
D. 0.301 mol L −1
Answer:
78. What volume of 5M N a2 SO4 must be added to 25 mL of
1M BaCl to produce 10 g of BaSO ?

2 4
A. 8.58 mL
B. 7.2 mL
C. 10 mL
D. 12 mL
Answer:
79. What will be the molarity of the solution in which 0.365 g
of HCl gas is dissolved in 100 mL of solution ?
A. 2 M
B. 0.2 M
C. 1 M
D. 0.1 M
Answer:
80. Which mode of concentration does not change with
temperature ?
A. Molarity
B. Normality
C. Molality
D. All of these
Answer:

81. What will be the molality of the solution made by
dissolving 10 g of NaOH in 100g of water ?
A. 2.5 m
B. 5 m
C. 10 m
D. 1.25 m
Answer:

82. What will be the molality of chloroform in the water
sample which contains 15 ppm chloroform by mass?
A. 1.25 × 10 −4
m
B. 2.5 × 10 −4
m
C. 1.5 × 10 −3
m
D. 1.25 × 10 −5
m
Answer:
Hots
1. 45.4L of dinitrogen reacted with 22.7L of dioxygen and 45.4
L of nitrous oxide was formed the reaction is given below
2N2 (g) + O2 (g) → 2N2 O(g)
Which law is being obeyed in this experiment? Write the
statement of the law?
A. Gay Lussac's law
B. Law of definite proportion
C. Law of multiple proportions
D. Avogadro's law
Answer:

2. Hydrogen gas is prepared in the laboratory by reacting
dilute HCl with granulated zinc, Following reaction takes
place
Zn + 2H Cl → ZnCl2 + H2
Calculate the voluem of hydrogen gas liberated at STP when
32.65 g of zinc reacts with HCl. 1 mol of a gas occupies 22.7 L
volume at STP, atomic mass of Zn=65 .3u
A. 10.03 L
B. 11.35 L
C. 11.57 L
D. 9.53 L
Answer:

3. Chemical reactions involve interaction of atoms and
molecules. A large number of atoms and molecules
(approximately 6.022 × 10
23
) are present in a few grams of
any chemical compound varying with their atomic/molecular
masses. To handle such a large number conveniently, the
mole concept was introduced. This concept has implications
in diverse areas such as analytical chemistry, biochemistry,
electrochemistry and radiochemistry. The following example
illustrate a typical case involving chemical/electrochemical
reaction which requires a clear understanding of mole
concept.
A 4.0 molar aqueous solution of NaCl is prepared and 500 mL
of the solution is electrolyzed. This lead to the evolution of
chlorine gas at one of the electrodes (atomic mass : Na = 23 ,

Hg = 200 , 1F = 96500 C)
The total number of moles of chlorine gas evolved is :
A. 0.5
B. 1
C. 2
D. 3
Answer:
23

electrochemistry adn radiochemistry. The following examples
concept.
of the solution is electrolysed. This lead to the evolution of
chlorine gas at one of electrodes (atomis mass : Na = 23 , Hg
= 200 , 1F = 96500 C)
If the cathode is a Hg electrode, the maximum weight (g) of
amalgam formed from the solution is :
A. 200
B. 225
C. 400
D. 446
Answer:
5. The total charge (coulombs) required for complete
electrolysis is
A. 24125
B. 48250
C. 96500
D. 193000
Answer:
6. A compound on analysis was found to contain the
following composition :
N a = 14.31 % , S = 9.97 % , O = 69.50 % and H = 6.22 %
Calculate the molecular formula of the compound assuming
that the whole of hydrogen in the compound is present as
water of crystallisation. Molecular mass of the compound is
322.
A. N a 2
SO4
B. N a 2
SO4 . 10H2 O
C. N a 2
SH10 O12
D. N a 2
SO4 . 7H2 O
Answer:
7. The reactant which is entirely consumed in reaction is
known as limiting reagent. In the reaction
2A + 4B → 3C + 4D , when 5 moles of A react with 6 moles
of B, then
(a) which is the limiting reagent?
(b) calculate the amount of C formed?
A. C, 4.5 mol
B. B, 4.5 mol
C. B, 3.5 mol
D. C, 4.0 mol
Answer:
8. The density of 3 molal solution of NaOH is 1.110g mL

−1
.
Calculate the molarity of the solution.
A. 2.69 M
B. 2.97 M
C. 4.57 M
D. 6.70 M
Answer: B
9. 1L of 0.1M N aOH , 1L of 0.1M KOH , and 2L of
0.05M Ba(OH )
2
are mixed togther. What is the final
concentration of the solution.
A. 0.01 M
B. 0.01 N
C. 0.1 N
D. 0.001 M
Answer:
Exemplar Problems
1. What will be the molarity of a solution, which contains
5.85g of N aCl(s) per 500mL?
A. 4 mol L −1
B. 20 mol L −1
C. 0.2 mol L −1
D. 2 mol L −1
Answer:
2. If 500mL of a 5M solution is diluted to 1500 mL, what will
be the molarity of the solution obtained?

A. 1.5 M
B. 1.66 M
C. 0.017 M
D. 1.59 M
Answer: B
3. The number of atoms present in one mole of an element is
equal to Avogadro number. Which of the following elements
contains the greatest number of atoms ?
A. 4 g He
B. 46 g Na
C. 0.4 g Ca
D. 12 g He
Answer:
4. If the concentration of glucose (C6 H12 O6 ) in blood is 0.9
gL −1
, what will be the molarity of glucose in blood?
A. 5 M
B. 50 M
C. 0.005 M
D. 0.5 M
Answer: C
5. What will be the molality of the solution containing 18.25 g
of HCl gas in 500 g of water ?
A. 0.1 m
B. 1 M
C. 0.5 m
D. 1 m
Answer:

6. One mole of any substance contains 6.022 × 10
23
atoms/molecules. Number of molecules of H 2

SO4 present in
100mL of 0.02M H 2
SO4 solution is
A. 12.044 × 10 20
B. 6.022 × 10 23
C. 1 × 10 23
D. 12.044 × 10 23
Answer:
7. The empirical formula and molecular mass of a compound
are CH 2
O and 180 g respectively. What will be the molecular
formula of the compound ?
A. C 9
H18 O9
B. CH 2
O
C. C 6
H12 O6
D. C 2
H4 O 2
Answer:
8. If the density of a solution is 3.12g mL

−1
, the mass of 1.5
mL solution in significant figures is
A. 4.7 g
B. 4680 × 10 −3
g
C. 4.680 g
D. 46.80 g
Answer:
9. Which of the following statements about a compound is
incorrect ?
A. A molecule of a compound has atoms of different
elements.
B. A compound cannot be separated into its constituent
elements by physical methods of separation.

C. A compound retains the physical properties of its
constituents elements.
D. The ratio of atoms of different elements in a
compound is fixed.
Answer:
10. Which of the following statements is correct about the
reaction given below:-
4F e(s) + 3O2 (g) → 2F e2 O3 (g)
A. Total mass of iron and oxygen in reactants = total mass
of iron and oxygen in product, therefore, it follows law

of conservation of mass.
B. Total mass of reactant = total mass of product,
therefore, law of multiple proportions is followed.
C. Amount of F e2 O3 can be increased by taking any one
of the reactants (iron or oxygen ) in axcess.
D. Amount of F e2 O3 produced will decreased if the
amount of any one of the reactants (iron or oxygen ) is
taken in excess.
Answer:
Nature Properties Of Matter And Their Measurements

1.
Choose the correct statement about I, II and III.
A. I and II have definite volume but III does not have this
property
B. I, II and III are interconvertible by changing the
conditions of temperature by pressure.
C. In the particles of I, freedom of movement is large.
D. Both (a) and (b)
Answer: D
2. Few quantities with their units are listed below. Mark the
units which are not correctly matched.
(i) Density : kg m −3
(ii) Velocity of light : m s −1
(iii) Planck's constant : J −1

s
−1
(iv) Acceleration : ms −2
A. (ii) and (iv)
B. (i) and (iii)
C. (iii) and (v)
D. (iv) and (v)
Answer:

3. Match the prefixes present in coloumn I with their
multiples in coloumn II and mark the appropriate choice.
A. (A) → (i), (B) → (ii), (C) → (iii), (D) → (iv)
B. (A) → (ii), (B) → (i), (C) → (iv), (D) → (iii)
C. (A) → (iv), (B) → (iii), (C) → (i), (D) → (ii)
D. (A) → (iii), (B) → (iv), (C) → (ii), (D) → (i)
Answer:

4. Mark the conversion factor which is not correct.
A. 1 atm = 1.01325 × 10
5
pa
B. 1 metre = 39.37 inches
C. 1 litre = 10
−3
m
3
D. 1 inch =3.33 cm
Answer:

5. Consider the following figure,
The correct relationship between fahrenheit and celsius scale
is
A. ∘
F =
∘
C + 273.15
2
B. ∘
F =
∘
C + 16
5
9
C. ∘
F =
∘
C + 32
5
1
D. ∘
F =
∘
C + 32
3
Answer:
Uncertainty Of Measurement
1. Few figures are expressed in scientific notation. Mark the
incorrect one.
A. 234000 = 2.34 × 10
5
B. 8008 = 8 × 10
3
C. 0.0048 = 4.8 × 10
−3
D. 500.0 = 5.00 × 10
2
Answer:
2. Markthe rule which is not correctly stated about
determination of significant figures.
A. Zeros preceding to first non-zero digit are not
significant.
B. Zero between two non-zero digits are not significant.
C. Zero at the end or right of the number are significant if
they are on the right side of decimal point.

D. All non - zero digits are significant.
Answer: B
3. Which of the following rules regarding the significant
figures and calculations involving them is not correct?
A. The result of an addition or subtraction is reported to
the same number of decimal places as present in
number with least decimal places.
B. Result of multiplication or division should have same
number of significant figures as present in most
precise figure.
C. The result of multiplication or division should be
rounded off to same number of significant figures as
present in least precise figure.
D. The non-significant figures in the measurements are
rounded off.
Answer:
4. The result of the operation 2.5 × 1.25 should be which of
the following on the basis of significant figures?
A. 3.125
B. 3.13
C. 3.1
D. 31.25
Answer:
5. How many significant figures are present in 0.010100 × 10

3
A. 7
B. 5
C. 3
D. 10
Answer: B
6. What will be the answer in appropriate significant figures
as a result of addition of 3.0223 and 5.041 ?
A. 80.633
B. 8.0633
C. 8.063
D. 806.33
Answer:

7. Which of the following is the most accurate measurement?
A. 9m
B. 9.0m
C. 9.00m
D. 9.000m
Answer:
8. Which set of figures will be obtained after rounding up the
following up to three significant figures?
34.216, 0.04597, 10.4107

A. 34.3, 0.0461, 10.4
B. 34.2, 0.0460, 10.4
C. 34.20, 0.460, 10.40
D. 34.21, 4.597, 1.04
Answer:
9. Which of the following option is not correct ?
A. 2.300+0.02017+0.02015=2.340
B. 126, 000 has 3 significant figures.
C. 15.15μs = 1.515 × 10
−5
s
D. 0.0048 = 48 × 10
−3
Answer:
10. What should be the volume of the milk (in m

3
) which
measures 5L?
A. 5 × 10 −3
m
3
B. 5 × 10
3
m
3
C. 5 × 1000m 3
D. 5 × 10
6
m
3
Answer:

11. How many seconds are there in 3 days?
A. 259200 s
B. 172800 s
C. 24800 s
D. 72000 s
Answer:
12. 18.72 g of a substance 'X' occupies 1.81 cm

3
. What will be
its density measured in correct significant figures?
A. 10.3gcm −3
B. 10.34gcm −3
C. 10.4gcm −3
D. 10.3425gcm −3
Answer:
Laws Of Chemical Combination
1. 4.88 g of KClO3 when heated produced 1.92 g of O2 and
2.96 g of KCl. Which of the following statements regarding
the experiment is correct?
A. The result illustrates the law of conservation of mass.

B. The result of illustrates the law of multiple
proportions.
C. The result illustrates the law of constant proportion.
D. None of the above laws is followed.
Answer:
2. How much mass of silver nitrates will react with 5.85 g of
sodium chloride to produce 14.35 g of silver chloride and 8.5
g of sodium nitrates if law of conservation of mass is
followed?
A. 22.85 g
B. 108 g
C. 17.0 g
D. 28.70 g
Answer: C
3. What mass of hydrochloric acid is needed to decompose
50 g of limestone?
A. 36.5 g
B. 73 g
C. 50 g
D. 100 g
Answer: A
4. Which one of the following best explains the law of
conservation of mass ? (a) 100 g of water is heated to give
steam. (b)A sample of N2 gas is heated at constant pressure
without any change in mass. (c)36 g of carbon combines with
32 g of oxygen to form 68 g of CO2 (d)10 g of carbon is
heated in vacume without any change in mass.
A. 100 g of water is heated to give steam.
B. A sample of N2 gas is heated at constant pressure
without any change in mass.

C. 36 g of carbon combines with 32 g of oxygen to form
68 g of CO 2
D. 10 g of carbon is heated in vacuume without any
change in mass.
Answer:
5. What mass of sodium chloride would be decomposed by
9.8 g of sulphuric acid if 12 g of sodium bisulphate and 2.75 g
of hydrogen chloride were produced in a reaction?
A. 14.75 g
B. 3.8 g
C. 4.95 g
D. 2.2 g
Answer: C
6. In an experiment 2.4g of iron oxide in reduction with
hydrogen gave 1.68 g of iron. In another experimet, 2.7 g of
iron oxide gave 1.89 g of iron on reduction. Which law is
illustrated from the above data?
A. Law of constant proportions
B. Law of multiple proportions
C. Law of reciprocal proportions

D. Law of conservation proportions
Answer:
7. The following data are obtained when dinitrogen and
dioxygen react together to form different compounds:
Which law of chemical combination is obeyed by the above
experimental data ?
A. Law of conservation of mass
B. Law of definite proportions

D. Avogadro's law
Answer:
8. Which of the following statements indicates that law of
multiple proportion is being followed?
A. An element forms two oxides, XO and XO2 containing
50% and 60% oxygen respectively. The ratio of masses
of oxygen which combines with 1 g of element is 2 : 3.
B. Hydrogen sulphide contains 5.89% hydrogen, water
contains 11.1% hydrogen and sulphur dioxyde contains

50% oxygen.
C. 3.47 g of BaCl2 reacts with 2.36g of N a2 SO4 to give
3.88 of BaSO and 1.95 g of NaCl.

4
D. 20mL of ammonia gives 10 volumes of N2 and 30
volumes of H at constant temperature and pressure.

2
Answer:
9. Which one of the following pairs of compound illustrates
the law of multiple proportion
A. P H 3
, H Cl
B. P bO, P bO 2
C. H 2
S, SO2
D. CuCl 2
, CuSO4
Answer: B
10. The statements for laws of chemical combinations are
given below. Mark the option which is not correctly matched.
A. Matter can neither be created nor destroyed: Law of
conservation of mass
B. A compound always contains exactly the same
proportions of elements by weight : Law of definite
proportions
C. When gases combine they do so in a simple ratio by
weight : Gay Lussac's Law
D. Equal volumes of gases at same temperature and
pressure contain same number of molecules:
Avogadro's Law
Answer:
11. Give below are few statements. Mark the statement which
is not correct.
A. Atoms are neigther created nor destroyed in a
chemical reaction.
B. Law of definite proportion state that a given
compound always contains exactly the same
proportion of elements by weight.
C. Gay Lussac's law of chemical combination is valid for all
substances.
D. A pure compund has always a fixed proportion of
masses of its constituents.
Answer:
12. A balanced equation for combustion of methane is given
below:
CH4 ( g ) + 2O2 ( g ) → CO2 ( g ) + 2H2 Og
Which of the following statements is not correct on the basis
of the above chemical equation? (A) one mole of CH4 reacts
with 2 moles of oxygen to give one mole of CO2 (B) one
molecule of CH4 reacts with 2 molecules of oxygen to give
one molecule of CO2 and 2 molecules of water (C) 22.4L
methane reacts with 44.8L of oxygen to give 44.8L of CO2
and 22.4L of water (D) 16g of methane reacts with 64g of O2
to give 44g of CO2 and 36g of water
A. One mole of CH reacts with 2 moles of oxygen to give

4
one mole of CO and 2 moles of water.

2
B. One molecules of CH4 reacts with 2 molecules of
oxygen to give one molecule of CO2 and 2 molecules
of water.
C. 22.4 L of methane reacts with 44.8 L of oxygen to give
44.8 L of CO and 22.4 L of water.

2
D. 16 g of methane reacts with 64 g of O to give 44 g of

2
CO2 and 36 g of water.
Answer:
13. Which of the following law of chemical combination is
satisfied by the figure?

A. Law of multiple proportion
B. Dalton's law
C. Avogadro law
D. Law of conservation of mass
Answer:

Atomic And Molecular Masses
1. The reference standard used for defining atomic mass is
A. H-1
B. C-12
C. C-13
D. C-14
Answer: B
2. Are the atomic masses of some elements actually
fractional ?
A. They exist as a mixture of isotopes of different masses
B. They contain impurities of other atoms
C. They are mixtures of isobars
D. They cannot be weighted accurately.
Answer: A
3. Oxygen occurs in nature as a mixture of isotopes
16
O,
17
O and
18
O having masses of 15.995 u, 16.999 u and
17.999 u and relative abundance of 99.763%, 0.037% and
0.200% respectively. What is the average atomic mass of
oxygen?
A. 15.999 u
B. 16.999 u
C. 17.999 u
D. 18.999 u
Answer: A
4. For every one 37

Cl isotopes there are three 35
Cl isotopes
in a sample of chlorine. What will be the average atomic
mass of chlorine?
A. 35
B. 37
C. 35.5
D. 35.6
Answer:
5. Carbon occur in nature as a mixture of C − 12 and C − 13
. Average atomic mass of carbon is 12.011 what is the %
abundance of C − 12 in nature ?
A. 0.889
B. 0.989
C. 0.899
D. 0.799
Answer:
6. Packing of Na
+
and Cl
−
ions in sodium chloride is
depicted by the given figure. Choose the correct option
regarding formula mass of sodium chloride.

(A) in solid
state, sodium chloride does not exist as a single entity (B)
formula mass of NaCl is 68.0u (C) formula mass of NaCl is the
sum of atomic masses of Na and Cl (D) both A and C
A. In the solid, sodium chloride does not exist as a single
entity.
B. Formula mass of NaCl is 68.0 u.
C. Formula mass of NaCl is the sum of atomic masses of
Na and Cl
D. Both (a) and (c)
Answer:
Mole Concept And Molecular Masses
1. What is the mass of carbon dioxide which contains the
same number of molecules as are contained in 40 g of
oxygen?
A. 40g
B. 55g
C. 32g
D. 44g
Answer: B
2. Match the coloumn I with coloum II and mark the
appropriate choice.
A. (A) → (ii), (B) → (i), (C) → (iv), (D) → (iii)
B. (A) → (i), (B) → (ii), (C) → (iii), (D) → (iv)
C. (A) → (iv), (B) → (iii), (C) → (i), (D) → (ii)
D. (A) → (iv), (B) → (iii), (C) → (ii), (D) → (i)
Answer:

3. The number of oxygen atoms present in 1 mole of oxalic
acids dihydrate is
A. 6 × 1023
B. 6.022 × 10 34
C. 7.22 × 10 23
D. 36.13 × 10 23
Answer: D
4. The measured density at NT P of He is 0.1784gL

−1
.
Calculate the weight of 1mole of H e.

A. 39.9 g
B. 22.4 g
C. 3.56 g
D. 29 g
Answer:
5. Which of the following gases will have least volume if 10g
of each gas is taken at same temperature and pressure?
A. CO 2
B. N2
C. CH 4
D. HCl
Answer:
6. How many number of molecules and atoms respectively
are presetn in 2.8 liters of a diatomics gas at STP ?
A. 6.023 × 10 23
B. 6.023 × 10 23
C. 7.5 × 10 22 22
, 15 × 10
D. 15 × 10 22
, 7.5 × 10
23
Answer:
7. Total number of atoms present in 34 g of N H is

3
A. 4 × 10 23
B. 4.8 × 10 21
C. 2 × 10 23
D. 48 × 10 23
Answer: D
8. What will be the mass of 100 atoms of hydrogen?
A. 100g
B. 1.66 × 10 − 22
g
C. 6.023 × 10 23
g
D. 100 × 6.023 × 10 23
g
Answer:
9. How many atoms in total are present in 1kg of sugar?
A. 7.92 × 10 25
atoms
B. 6 × 1023
atoms
C. 6.022 × 10 25
atoms
D. 1000 atoms
Answer:
10. 1.4 moles of phosphorus trichloride are present in a
sample. How many atoms are there in the sample?
A. 5.6
B. 34
C. 2.4 × 10
23
D. 3.372 × 10 24
Answer:

11. What will be the standard molar volume of He, if its
density is 0.1784 g/L at STP?
A. 11.2 L
B. 22.4 L
C. 5.6 L
D. 2.8 L
Answer:
12. In a mixture of gases, the volume content of a gas is
0.06% at STP. Calculate the number of molecules of the gas
in 1 L of the mixture.
A. 1.613 × 10 23
B. 6.023 × 10 23
C. 1.61 × 10
27
D. 1.61 × 10
19
Answer:
13. What will be the weight of CO having the same number of
oxygen atoms at present in 22 g of CO ?

2
A. 28g
B. 22g
C. 44g
D. 72g
Answer:
14. Match the mass of elements given in coloumn I with the
no. of moles given in column II and mark the appropriate
choice.
A. (A) → (iv), (B) → (iii), (C) → (ii), (D) → (i)
B. (A) → (i), (B) → (iii), (C) → (ii), (D) → (iv)

C. (A) → (iii), (B) → (ii), (C) → (i), (D) → (iv)
D. (A) → (ii), (B) → (i), (C) → (iv), (D) → (iii)
Answer:
15. Calculate the number of aluminium ions present in 0.051
g of aluminium oxide.
(Hint: The mass of an ion is the same as that of an atom of
the same element. Atomic mass of Al = 27 u)
A. 6.023 × 10 20
ions
B. 3 ions
C. 6.023 × 10 23
ions
D. 9 ions
Answer:
16. Which of the following correctly represents 180 g of water
5 moles of water
(ii) 10 moles of water
(iii) 6.023 × 10 23
molecules of water
(iv) 6.023 × 10 24
molecules of water
A. (i) and (ii)
B. (i) and (iv)
C. (ii) and (iv)

D. (ii) and (iii)
Answer:
17. How many oxygen atoms will be present in 88 g of CO ?

2
A. 24.08 × 10 23
B. 6.023 × 10 23
C. 44 × 10 23
D. 22 × 10 24
Answer: A

18. Calculate the total number of electrons present in 1.6 g of
methane
A. 6.023 × 10 23
B. 16
C. 12.04 × 10 23
D. 6.023 × 10 24
Answer:
19. A mixture having 2 g of hydrogen and 32 oxygen occupies
how much volume at NTP?

A. 44.8 L
B. 22.4 L
C. 11.2 L
D. 76.2 L
Answer:
20. One atom of an element weight 3.32 × 10

− 23
g. How
many number of gram atoms are in 20 kg of the element?
A. 2000
B. 20
C. 200
D. 1000
Answer:
21. Fill in the blanks by choosing the correct option.
22. The mass of one mole of a substance in grams is called its

A. Molecular mass
B. Molar mass
C. Avogadro's mass
D. Formula mass.
Answer:
23. How much copper is present in 50 g of CuSO 4
A. 19.90 g
B. 39.81 g
C. 63.5 g
D. 31.71 g
Answer:
Percentage Composition
1. 0.48 g of a sample of a compound containing boron and
oxygen contains 0.192 g of boron and 0.288 g of oxygen.
What will be the percentage composition of the compound?
A. 60% and 40% B and O respectively
B. 40% and 60% B and O respectively
C. 30% and 70% B and O respectively
D. 70% and 30% B and O respectively

Answer: B
2. A compound of magnesium contains 21.9% magnesium,
27.8% phosphorus and 50.3% oxygen. What will be the
simplest formula of the compound?
A. M g
2
P2 O7
B. M gP O 3
C. M g
2
P2 O2
D. M gP 2
O4
Answer: A

3. A compound contains two elements 'X' and 'Y' in the ratio
of 50% each. Atomic mass 'X' is 20 and 'Y' is 40. what can be
its simplest formula?
A. XY
B. X 2
Y
C. XY 2
D. X 2
Y3
Answer: B

4. The empirical formula of a compound is CH2 O2 . What
could be its molecular formula?
A. C2
H2 O 2
B. C2
H2 O 4
C. C2
H4 O 4
D. CH 4
O4
Answer: C
5. A gas has molecular formula (CH )

n
. If vapour density of
the gas is 39, what should be the formula of the compound ?

A. C 3
H3
B. C 4
H4
C. C 2
H2
D. C 6
H6
Answer:
6. Determine the molecular formula of an oxide of iron in
which the mass percent of iron and oxygen are 69.9 and ,
30.1
respectively.
A. FeO
B. F e 3
O4
C. F e 2
O3
D. F eO 2
Answer:
7. An organic compound on analysis gave C=54.2%, H=9.2% by
mass. Its empirical formula is
A. CH O 2
B. CH 2
O
C. C2
H8 O
D. C2
H4 O
Answer:
8. The relative number of mass of elements, 'X' and 'Y' in a
compound is 0.25 and 0.5. The empirical formula of
compound is
A. XY
B. X 2
Y
C. XY 2
D. X 2
Y2
Answer:

9. Two elements 'P' and 'Q' combine to form a compound.
Atomic mass of 'p' is 12 and 'Q' is 16. percentage of 'P' in the
compound is 27.3. What will be the empirical formula of the
compound ?
A. P 2
Q2
B. PQ
C. P 2
Q
D. P Q 2
Answer:
Stoichiometry And Stoichiometry Calculations

1. 1g of Mg is burnt in a closed vessel which contains
0.5gofO2
(i) Which reactants is left in excess
(ii) Find the mass of the excess reactant.
A. O is a limiting reagent and Mg is in excess by 0.25 g.

2
B. Mg is a limiting reagent and is in excess by 0.5 g.
C. O is a limiting reagent and is in excess by 0.25 g.

2
D. O is a limiting reagent and Mg is in excess by 0.75 g.

2
Answer:

2. In a reaction container, 100g of hydrogen and 100 g of Cl 2
are mixed for the formation of HCl gas. What is the limiting
reagent and how much HCl is formed in the reaction ?
A. H is limiting reagent and 36.5 g of HCl are formed.

2
B. Cl is limiting reagent and 102.8 g of HCl are formed.

2
C. H is limiting reagent and 142 g of HCl are formed.

2
D. Cl is limiting reagent and 73 g of HCl are formed.

2
Answer:
3. If 40g of CaCO3 is treated with 40g of HCl, which of the
reactants will acts as limiting reagent?

A. CaCO 3
B. HCl
C. Both (a) and (b)
D. None of these
Answer:
4. The weight of AgCl precipitated when a solution
containing 5.85 g of NaCl is added to a solution containing
3.4g of AgN O is 3
A. 28g
B. 9.25g
C. 2.870g
D. 58g
Answer:
5. How much oxygen is required for complete combustion of
560 g of ethene?
A. 6.4 kg
B. 1.92 Kg
C. 2.8 kg
D. 9.6 kg
Answer:
6. How many moles of oxygen gas can be produced during
electricity decomposition of 180 g of water ?
A. 2.5 moles
B. 5 moles
C. 10 moles
D. 7 moles
Answer:

7. How many grams of CaO are required to neutralise 852g
of P 4
O10 ? Draw the structure of P 4
O10 .
A. 852g
B. 1008g
C. 85g
D. 7095g
Answer:
8. What volume of dioxygen is required for complete
combustion of 2 volume of acetylene gas at NTP ?

A. 2 volumes
B. 5 volumes
C. 10 volumes
D. 4 volumes
Answer:
9. What quantity of copper(II) oxide will react 2.80litre of
hydrogen at NTP
A. 79.5 g
B. 2 g
C. 9.9 g
D. 22.4 g
Answer:
10. At NTP, 1L of O reacts with 3L of carbon monoxide. What

2
will be the volume of CO and CO after the reaction?

2
A. 1L CO , 1L CO
2
B. 2L CO , 2L CO
2
C. 1L CO , 2L CO
2
D. 2L CO , 1L CO
2
Answer:
11. Calcium carbonate decomposes on heating to give
calcium oxide and carbon dioxide. How much volume of CO 2
will be obtained by thermal decomposition of 50g CaCO ?

3
A. 1L
B. 11.2 L
C. 44 L
D. 22.4 L
Answer:

12. Chlorine gas is prepared by reaction of H2 SO4 with
M nO2 and NaCl. What volume of Cl will be produced at STP

2
if 50 g of NaCl is taken in the reaction ?
A. 1.915 L
B. 22.4 L
C. 11.2 L
D. 9.57 L
Answer:
13. HCl is produced in the stomach which can be neutralised
by M g(OH )
2
in the form of milk of magnesia. How much
M g(OH )
2
is required to neutralise one mole of stomach
acid?
A. 29.16 g
B. 34.3 g
C. 58.33 g
D. 68.66g
Answer:
14. Magnetite, F e 3
O4 , can be converted into metallic iron by
heating with carbon monoxide as represented by this
equation:
F e3 O4 (s) + CO(g) → F e(s) + CO2 (g)

The kilograms of F e 3
O4 which must be processed in this way
to obtain 5.00kg of iron, if the process is 85 % efficient is
closest to? [M : = F e = 56]
A. 8.12 kg
B. 4.14 kg
C. 6.94 kg
D. 16.8 kg
Answer:
15. What is the mass percent of oxygen in ethanol ?
A. 0.5214
B. 0.1313
C. 0.16
D. 0.3473
Answer:
16. How much mass of sodium acetate is required to make
250 mL of 0.575 molar aqueous solution?
A. 11.79 g
B. 15.38 g
C. 10.81 g
D. 25.35 g
Answer:
17. A solution is prepared by adding 5g of a solute 'X' to 45 g
of solvent 'Y'. What is the mass percent of the solute 'X' ?
A. 0.1
B. 0.111
C. 0.9
D. 0.75
Answer:

18. A 1.50g sample of an ore containing silver was dissolved,
and all of the Ag

+
was converted to 0.125 g of Ag2 S . What
was the percentage of silver in the ore?
A. 0.216
B. 0.072
C. 0.017
D. 0.248
Answer:
19. 2.82g of glucose is dissolved in 30g of water. The mole
fraction of glucose in the solution is

A. 0.01
B. 0.99
C. 0.52
D. 1.66
Answer:
20. What volume of water is to be added to 100 cm of 0.5M

3
NaOH solution to make it 0.1 M solution?
A. 200cm 3
B. 400cm 3
C. 500cm 3
D. 100cm 3
Answer:
21. The final molarity of a solution made by mixing 50 mL of
0.5 M HCl, 150 mL of 0.25 M HCl and water to make the
volume 250 mL is
A. 0.5 M
B. 1M
C. 0.75 M
D. 0.25 M
Answer:
22. A solution is made by dissolving 49g of H 2

SO4 in 250 mL
of water. The molarity of the solution prepared is
A. 2 M
B. 1 M
C. 4 M
D. 5 M
Answer:

23. What is the concertration of copper sulphate (in mol
L
−1
) if 80 of it is dissolved in enough water to make a final
volume of 3 L?
A. 0.0167
B. 0.167
C. 1.067
D. 10.67
Answer:
24. 4.28g of NaOH is dissolved in water and the solution is
made to 250 cc. what will be the molarity of the solution ?

A. 0.615 mol L −1
B. 0.428 mol L −1
C. 0.99 mol L −1
D. 0.301 mol L −1
Answer:
25. What volume of 5M N a2 SO4 must be added to 25 mL of
1M BaCl to produce 10 g of BaSO ?

2 4
A. 8.58 mL
B. 7.2 mL
C. 10 mL
D. 12 mL
Answer:
26. What will be the molarity of the solution in which 0.365 g
of HCl gas is dissolved in 100 mL of solution ?
A. 2 M
B. 0.2 M
C. 1 M
D. 0.1 M
Answer:
27. What will be the molality of the solution made by
dissolving 10 g of NaOH in 100g of water ?
A. 2.5 m
B. 5 m
C. 10 m
D. 1.25 m
Answer:

28. What will be the molality of chloroform in the water
sample which contains 15 ppm chloroform by mass?
A. 1.25 × 10 −4
m
B. 2.5 × 10 −4
m
C. 1.5 × 10 −3
m
D. 1.25 × 10 −5
m
Answer:
Higher Order Thinking Skills

1. 45.4L of dinitrogen reacted with 22.7L of dioxygen and 45.4
L of nitrous oxide was formed the reaction is given below
2N2 (g) + O2 (g) → 2N2 O(g)
Which law is being obeyed in this experiment? Write the
statement of the law?
A. Gay Lussac's law
B. Law of definite proportion
D. Avogadro's law
Answer:

2. Hydrogen gas is prepared in the laboratory by reacting
dilute HCl with granulated zinc, Following reaction takes
place
Zn + 2H Cl → ZnCl2 + H2
Calculate the voluem of hydrogen gas liberated at STP when
32.65 g of zinc reacts with HCl. 1 mol of a gas occupies 22.7 L
volume at STP, atomic mass of Zn=65 .3u
A. 10.03 L
B. 11.35 L
C. 11.57 L
D. 9.53 L
Answer:

23
electrochemistry and radiochemistry. The following example
concept.
of the solution is electrolyzed. This lead to the evolution of
chlorine gas at one of the electrodes (atomic mass : Na = 23 ,

Hg = 200 , 1F = 96500 C)
The total number of moles of chlorine gas evolved is :
A. 0.5
B. 1
C. 2
D. 3
Answer:
23

electrochemistry adn radiochemistry. The following examples
concept.
of the solution is electrolysed. This lead to the evolution of
chlorine gas at one of electrodes (atomis mass : Na = 23 , Hg
= 200 , 1F = 96500 C)
If the cathode is a Hg electrode, the maximum weight (g) of
amalgam formed from the solution is :
A. 200
B. 225
C. 400
D. 446
Answer:
5. The total charge (coulombs) required for complete
electrolysis is
A. 24125
B. 48250
C. 96500
D. 193000
Answer:
6. A compound on analysis was found to contain the
following composition :
N a = 14.31 % , S = 9.97 % , O = 69.50 % and H = 6.22 %
Calculate the molecular formula of the compound assuming
that the whole of hydrogen in the compound is present as
water of crystallisation. Molecular mass of the compound is
322.
A. N a 2
SO4
B. N a 2
SO4 . 10H2 O
C. N a 2
SH10 O12
D. N a 2
SO4 . 7H2 O
Answer:
7. The reactant which is entirely consumed in reaction is
known as limiting reagent. In the reaction
2A + 4B → 3C + 4D , when 5 moles of A react with 6 moles
of B, then
(a) which is the limiting reagent?
(b) calculate the amount of C formed?
A. C, 4.5 mol
B. B, 4.5 mol
C. B, 3.5 mol
D. C, 4.0 mol
Answer:
8. The density of 3 molal solution of NaOH is 1.110g mL

−1
.
Calculate the molarity of the solution.
A. 2.69 M
B. 2.97 M
C. 4.57 M
D. 6.70 M
Answer: B
9. 1L of 0.1M N aOH , 1L of 0.1M KOH , and 2L of
0.05M Ba(OH )
2
are mixed togther. What is the final
concentration of the solution.
A. 0.01 M
B. 0.01 N
C. 0.1 N
D. 0.001 M
Answer:
Ncert Exemplar
1. Two students performed the same experiment separately
and each one of them recovered two readings of mass which
are given below. Correct reading of mass is 3.0 g. On the
basis of given data, mark the correct optioin out of the
following statements.
A. Results of both the students are neither accurate nor
precise.
B. Results of student A are both precise and accurate.
C. Results of student B are neither precise nor accurate.
D. Results of student B are both precise and accurate.

Answer:
2. What will be the molarity of a solution, which contains
5.85g of N aCl(s) per 500mL?
A. 4 mol L −1
B. 20 mol L −1
C. 0.2 mol L −1
D. 2 mol L −1
Answer:

3. If 500mL of a 5M solution is diluted to 1500 mL, what will
be the molarity of the solution obtained?
A. 1.5 M
B. 1.66 M
C. 0.017 M
D. 1.59 M
Answer: B
4. The number of atoms present in one mole of an element is
equal to Avogadro number. Which of the following elements
contains the greatest number of atoms ?

A. 4 g He
B. 46 g Na
C. 0.4 g Ca
D. 12 g He
Answer:
5. If the concentration of glucose (C6 H12 O6 ) in blood is 0.9
gL −1
, what will be the molarity of glucose in blood?
A. 5 M
B. 50 M
C. 0.005 M
D. 0.5 M
Answer: C
6. What will be the molality of the solution containing 18.25 g
of HCl gas in 500 g of water ?
A. 0.1 m
B. 1 M
C. 0.5 m
D. 1 m
Answer:
7. One mole of any substance contains 6.022 × 10

23
atoms/molecules. Number of molecules of H 2

SO4 present in
100mL of 0.02M H 2
SO4 solution is
A. 12.044 × 10 20
B. 6.022 × 1023
C. 1 × 10
23
D. 12.044 × 10 23
Answer:

8. The empirical formula and molecular mass of a compound
are CH 2
O and 180 g respectively. What will be the molecular
formula of the compound ?
A. C 9
H18 O9
B. CH 2
O
C. C 6
H12 O6
D. C 2
H4 O 2
Answer:
9. If the density of a solution is 3.12g mL

−1
, the mass of 1.5
mL solution in significant figures is

A. 4.7 g
B. 4680 × 10 −3
g
C. 4.680 g
D. 46.80 g
Answer:
10. Which of the following statements about a compound is
incorrect ?
A. A molecule of a compound has atoms of different
elements.
B. A compound cannot be separated into its constituent
elements by physical methods of separation.
C. A compound retains the physical properties of its
constituents elements.
D. The ratio of atoms of different elements in a
compound is fixed.
Answer:
11. Which of the following statements is correct about the
reaction given below:-
4F e(s) + 3O2 (g) → 2F e2 O3 (g)

A. Total mass of iron and oxygen in reactants = total mass
of iron and oxygen in product, therefore, it follows law
of conservation of mass.
B. Total mass of reactant = total mass of product,
therefore, law of multiple proportions is followed.
C. Amount of F e2 O3 can be increased by taking any one
of the reactants (iron or oxygen ) in axcess.
D. Amount of F e2 O3 produced will decreased if the
amount of any one of the reactants (iron or oxygen ) is
taken in excess.
Answer:

Assertion And Reason
1. Assertion: Solid have definite volume and shape.
Reason : In solid, the constituent particles are very close to
each other and there is not much freedom of movement.
A. If both assertion and reason are true and reason is the
correct explanation of assertion
B. If both assertion and reason are true but reason is not
correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.
Answer:

2. Assertion: On heating, a solid usually change to a liquid
and the liquid on further heating change to the gaseous
state.
Reason : Arrangement of constituent particles is different in
solid, liquid and gaseous state.
Answer:
3. Assertion : Components of a homogeneous mixture cannot
be separated by using physical methods
Reason : Composition of homogeneous mixture is uniform
throughtout as the components react to form a single
compound.

Answer:
4. Assertion: Elements and compound are the examples of
pure substances.
Reason : The properties of a compound are different from
those of its constituent elements.

Answer:
5. Assertion: The mass of a substance is constant whereas its
weight may vary from one place to another.
Reason : Mass of a substance is the amount of matter
present in it while weight is the force exerted by gravity on
an object.

Answer:
6. Assertion : Temperature below 0

∘
C is possible on celsius
scale but in Kelvin scale negative temperature is not possible
Reason : The Kelvin scale is related to celsius scale as
K = .
∘
.
C − 273

Answer:
View Text Solution
7. Assertion: Scientific notation for the number 100 is
expressed as 1 × 10 2
Reason : The number 1 × 10 has two significant figures.

2

Answer:
8. Assertion: Matter can neither be created nor be destroyed.
Reason : This is law of definite proportions.

Answer: C
9. Assertion: 12 parts by mass of carbon in CO and CO2
molecules combine with 16 and 32 parts by mass of oxygen.
Reason : A given compound always contains exactly the same
proportion of elemetns by weight.

Answer:
10. Assertion(A) One atomic mass unit is defined as one
twelth of the mass of one carbon-12 atom.
Reason(R) Carbon-12 isotope is the most abundant isotope
of carbon and has been chosen as standard.

Answer:
11. Assertion: One mole of a substance always contain the
same number of entities, no metter what the substance may
be.
Reason : One mole is the amount of a substance that
contains as many particles or entities as there are atoms in
exactly 12 g of the 12
C isotope.
Answer:
12. Assertion: Molecular formula shows the exact number of
different types of atoms present in a molecule of a
compound.
Reason : Molecular formula can be obtained directly from

empirical formula which represents the simplest whole
number ratio of various atoms present in a compound.
Answer:

13. Assertion: The reactant which is present in large amount
limits the amount of product formed is called limiting
reagent.
Reason : Amount of product formed does not depend upon
the amount of reactants taken.
Answer:

14. Assertion: Molarity of a solution does not depend upon
temperature whereas molality depends.
Reason : Molarity and molality both depend only on the
number of moles of solute particles.
Answer:
15. Assertion: In laboratory, a solution of a desired
concentration is prepared by diluting a stock solution.
Reason : Stock solution is the solution of higher
concentration.
Answer:

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CHEMISTRY

BOOKS - MTG CHEMISTRY (ENGLISH)

SOME BASIC CONCEPTS OF CHEMISTRY

units which are not correctly matched.

(ii) Velocity of light : m s −1

(iii) Planck's constant : J −1

B. (i) and (iii)

C. (iii) and (v)

D. (iv) and (v)

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2. Mark the conversion factor which is not correct.

B. 1 metre = 39.37 inches

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3. Few figures are expressed in scientific notation. Mark the

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determination of significant figures.

A. Zeros preceding to first non-zero digit are not

B. Zero between two non-zero digits are not significant.

C. Zero at the end or right of the number are significant if

they are on the right side of decimal point.

D. All non - zero digits are significant.

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figures and calculations involving them is not correct?

A. The result of an addition or subtraction is reported to

the same number of decimal places as present in

number with least decimal places.

B. Result of multiplication or division should have same

number of significant figures as present in most

C. The result of multiplication or division should be

rounded off to same number of significant figures as

present in least precise figure.

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6. The result of the operation 2.5 × 1.25 should be which of

the following on the basis of significant figures?

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7. How many significant figures are present in 0.010100 × 10

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as a result of addition of 3.0223 and 5.041 ?

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9. Which of the following is the most accurate measurement?

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10. Which of the following option is not correct ?

B. 126, 000 has 3 significant figures.

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11. What should be the volume of the milk (in m

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13. 18.72 g of a substance 'X' occupies 1.81 cm

its density measured in correct significant figures?

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14. 4.88 g of KClO when heated produced 1.92 g of O and

2.96 g of KCl. Which of the following statements regarding

the experiment is correct?

A. The result illustrates the law of conservation of mass.

B. The result of illustrates the law of multiple

D. None of the above laws is followed.

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sodium chloride to produce 14.35 g of silver chloride and 8.5

g of sodium nitrates if law of conservation of mass is

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