(

(c) Pieces of copper (d) Candle

4. Which of the following substances cannot be separated in

to its constituents by physical methods?

(a) Sugar and water solution

(b) Salt and sugar

(c) Solid glucose

(d) Both (a) and (b)

5. Which of the following pair of substances contain

element and compound within a pair ?

(A) O2, CH4 (B) H2, O2

(C) N2, CO2 (D) Na, CO

(a) A, C, D (b) B only

(c) C and D (d) All of these

6. 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

constituent elements.

(d) The ratio of atoms of different elements in a compound

is fixed.

7. Choose the correct combination

Element Compound Mixture

(a) Ammonia Sodium Air

(b) Water Sugar Aqueous sugar solution

(c) Hydrogen Oxygen Water

(d) Silver Water Air

SOME BASIC CONCEPTS OF

CHEMISTRY

8. Choose the correct statement.

(a) The particle s in liquids are more closely held than

gases but less free to move than solids.

(b) The particles of solids are arranged in orderly fashion

but they can move as freely as liquids.

(c) The particles of gases are far apart as compared to

solids and liquids and their movement is easy and

fast.

(d) The particles of gases moves faster than liquids only

when the gases are heated.

9. A mixture contains two or more substances in ________

which are called its ________.

(a) fixed ratio, compounds

(b) fixed ratio, elements

(c) any ratio, components

(d) any ratio, elements

10. Which one of these is not a pure compound?

(a) O3 (b) H2O2

(c) H2O (d) Sucrose solution

11. One fermi is

(a) 10–15 cm (b) 10–13 cm

(c) 10–10 cm (d) 10–12 cm

12. The prefix 1018 is

(a) giga (b) kilo

(c) exa (d) nano

13. The prefix zepto stands for (in m)

(a) 109 (b) 10–12

(c) 10–15 (d) 10–21

14. The unit J Pa–1 is equivalent to

(a) m3 (b) cm3

(c) dm3 (d) None of these

15. Which has highest weight ?

(a) 1 m3 of water (b) A normal adult man

(c) 10 litre of Hg (d) All have same weight

16. Which one of the following set of units represents the

smallest and largest amount of energy respectively?

(a) J and erg (b) erg and cal

(c) cal and eV (d) eV and L-atm

2 SOME BASIC CONCEPTS OF CHEMISTRY

17. A measured temperature on Fahrenheit scale

is 200 °F. What will this reading be on Celsius scale ?

(a) 40° C (b) 94° C

(c) 93.3 °C (d) 30° C

18. Which of the following is not a SI unit?

(a) metre (b) candela

(c) mole (d) litre

19. The prefix 10–24 is

(a) yotta (b) zeta

(c) yocto (d) zepto

20. Many countries use Fahrenheit scale for expressing

temperature of atmosphere. If temperature in any such

country is measured 41°F then what is its value in celcius

scale and would you expect hot or cold atmosphere in that

country?

(a) 15°C, cold (b) 25°C, normal

(c) 5°C, cold (d) 41°C, hot

21. A sample was weighted using two different balances. The

results were

(i) 3.929 g (ii) 4.0 g

How would the weight of the sample be reported?

(a) 3.93 g (b) 3g

(c) 3.9 g (d) 3.929 g

22. Two students performed the same experiment separately

and each one of them recorded 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 option out of the

following statements.

Students Readings

(i) (ii)

A 3.01 2.99

B 3.05 2.95

(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.

23. 0.00016 can be written as ...A... in scientific notaiton. Here,

A refers to

(a) 1.6 × 10–4 (b) 24.50 × 10–9

(c) 2.450 × 10–8 (d) 24.50 × 10–7

24. If the true value for an experimental result is 6.23 and the

results reported by three students X, Y and Z are :

X : 6.18 and 6.28

Y : 6.20 and 6.023

Z : 6.22 and 6.24

Which of the following option is correct :

(a) X precise, Y accurate, Z precise and accurate.

(b) X precise and accurate, Y not precise, Z precise

(c) Both X & Z precise & accurate, Y not precise.

(d) Both X & Y neither precise nor accurate, Z both precise

and accurate.
25. In the final answer of the expression

1.37

(29.2 􀀐 20.2) (1.79􀁵105 )

the number of significant figures is :

(a) 1 (b) 2

(c) 3 (d) 4

26. The number of significant figures for the three numbers

161 cm, 0.161 cm, 0.0161 cm are

(a) 3,4 and 5 respectively (b) 3,4 and 4 respectively

(c) 3,3 and 4 respectively (d) 3,3 and 3 respectively

27. Given P = 0.0030m, Q = 2.40m, R = 3000m, Significant figures

in P, Q and R are respectively

(a) 2, 2, 1 (b) 2, 3, 4

(c) 4, 2, 1 (d) 4, 2, 3

28. If the density of a solution is 3.12 g 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

29. In which of the following number all zeros are significant?

(a) 0.0005 (b) 0.0500

(c) 50.000 (d) 0.0050

30. The correctly reported answer of addition of 29.4406, 3.2

and 2.25 will have significant figures

(a) 3 (b) 4

(c) 2 (d) 5

31. The number of significant figures in 10.3106 g is

(a) 2 (b) 3

(c) 1 (d) 6

32. Choose the correct option that represents the result of the

given calculation to the appropriate number of significant

figures:
43.0 0.0243

0.340 4

(a) 0.768 (b) 0.77

(c) 0.76 (d) 0.7683

33. Arrange the numbers in increasing no. of significant figures.

0.002600, 2.6000, 2.6, 0.260

(a) 2.6 < 0.260 < 0.002600 < 2.6000

(b) 2.6000 < 2.6 < 0.002600 < 0.260

(c) 0.260 < 2.6 < 0.002600 < 2.6000

(d) 0.002600 < 0.260 < 2.6 < 2.6000

34. Dimension of pressure are same as that of

(a) Energy (b) Force

(c) Force per unit volume (d) Energy per unit volume

35. n g of substance X reacts with m g of substance Y to form

p g of substance R and q g of substance S. This reaction

can be represented as, X + Y = R + S. The relation which

can be established in the amounts of the reactants and the

products will be

(a) n – m = p – q (b) n + m = p + q

(c) n = m (d) p = q

EBD_7207

SOME BASIC CONCEPTS OF CHEMISTRY 3

36. 20 g of CaCO3 on heating gave 8.8 g of CO2 and 11.2 g of

CaO. This is in accordance with

(a) The law of conservation of mass.

(b) The law of constant composition.

(c) The law of reciprocal proportion.

(d) None of these

37. Which of the following is the best example of law of

conservation of mass?

(a) 12 g of carbon combines with 32 g of oxygen to form

44 g of CO2

(b) When 12 g of carbon is heated in a vacuum there is no

change in mass

(c) A sample of air increases in volume when heated at

constant pressure but its mass remains unaltered

(d) The weight of a piece of platinum is the same before

and after heating in air

38. Which of the following statements is correct about the

reaction given below ?

4Fe(s) 􀀎 3O2 (g) 􀁿􀁿􀁯2Fe2O3(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 reactants = total mass of product;

therefore, law of multiple proportions is followed.

(c) Amount of Fe2O3 can be increased by reducing the

amount of any one of the reactants (iron or oxygen).

(d) Amount of Fe2O3 produced will decrease if the amount

of any one of the reactants (iron or oxygen) is taken in

excess.

39. In an experiment 4.2 g of NaHCO3 is added to a solution of

acetic acid weighing 10.0 g, it is observed that 2.2 g of CO2

is released into the atmosphere. The residue left behind is

found to weigh 12.0 g

The above observations illustrate

(a) law of definite proportions.

(b) law of conservation of mass

(c) law of multiple proportions

(d) None of these

40. In one experiment, 4g of H2 combine with 32g of O2 to form

36g of H2O. In another experiment, when 50g of H2 combine

with 400g of O2 then 450g of H2O is formed. Above two

experiments follow

(a) The law of conservation of mass

(b) The law of constant composition

(c) Both (a) and (b)

(d) Neither (a) nor (b)

41. Irrespective of the source, pure sample, of water always yields

88.89% mass of oxygen and 11.11% mass of hydrogen. This is

explained by the law of

(a) conservation of mass (b) multiple proportions

(c) constant composition (d) constant volume

42. The percentage of copper and oxygen in samples of CuO

obtained by different methods were found to be the same.

The illustrate the law of

(a) constant proportions (b) conservation of mass

(c) multiple proportions (d) reciprocal proportions

43. The law of definite proportions was given by –

(a) John Dalton (b) Humphry Davy

(c) Proust (d) Michael Faraday

44. Which one of the following pairs of compounds illustrate

the law of multiple proportions ?

(a) H2O and Na2O (b) MgO and Na2O

(c) Na2O and BaO (d) SnCl2 and SnCl4

45. Among the following pairs of compounds, the one that

illustrates the law of multiple proportions is

(a) NH3 and NCl3 (b) H2S and SO2

(c) CS2 and FeSO4 (d) CuO and Cu2O

46. Two samples of lead oxide were separately reduced to

metallic lead by heating in a current of hydrogen. The weight

of lead from one oxide was half the weight of lead obtained

from the other oxide. The data illustrates

(a) law of reciprocal proportions

(b) law of constant proportions

(c) law of multiple proportions

(d) law of equivalent proportions

47. In compound A, 1.00g of nitrogen unites with 0.57g of

oxygen. In compound B, 2.00g of nitrogen combines with

2.24g of oxygen. In compound C, 3.00g of nitrogen combines

with 5.11g of oxygen. These results obey the following law

(a) law of constant proportion

(b) law of multiple proportion

(c) law of reciprocal proportion

(d) Dalton’s law of partial pressure

48. Which of the following statements indicates that law of

multiple proportion is being followed.

(a) Sample of carbon dioxide taken from any source will

always have carbon and oxygen in the ratio 1 : 2.

(b) Carbon forms two oxides namely CO2 and CO, where

masses fo oxygen which combine with fixed mass of

carbon are in the simple ration 2 : 1.

(c) When magnesium burns in oxygen, the amount of

magnesium taken for the reaction is equal to the amount

of magnesium in magnesium oxide formed.

(d) At constant temperature and pressure 200 mL of

hydrogen will combine with 100 mL oxygen to produce

200 mL of water vapour.

49. The molecular weight of O2 and SO2 are 32 and 64

respectively. At 15°C and 150 mm Hg pressure, one litre of

O2 contains ‘N’ molecules. The number of molecules in two

litres of SO2 under the same conditions of temperature and

pressure will be :

(a) N/2 (b) 1N

(c) 2N (d) 4N

4 SOME BASIC CONCEPTS OF CHEMISTRY

50. 10 dm3 of N2 gas and 10 dm3 of gas X at the same

temperature contain the same number of molecules, the gas

X is

(a) CO2 (b) CO

(c) H2 (d) NO

51. One mole of a gas occupies a volume of 22.4 L. This is

derived from

(a) Berzelius’ hypothesis (b) Gay-Lussac’s law

(c) Avogadro’s law (d) Dalton’s law

52. One of the following combination which illustrates the law

of reciprocal proportions ?

(a) N2O3, N2O4, N2O5 (b) NaCl, NaBr, NaI

(c) CS2, CO2, SO2 (d) PH3, P2O3, P2O5

53. Equal volumes of two gases A and B are kept in a container

at the same temperature and pressure. Avogadro’s law is

invalid if

(a) the gases are reactive

(b) the gases are non-reactive

(c) gas A has more number of molecules than gas B.

(d) None of these

54. Molecular mass is defined as the

(a) mass of one atom compared with the mass of one

molecule

(b) mass of one atom compared with the mass of one atom

of hydrogen

(c) mass of one molecule of any substance compared with

the mass of one atom of C-12

(d) None of the above

55. 1 amu is equal to

(a)

14

of O-16 (b)

12

of C-12

(c) 1 g of H2 (d) 1.66 × 10–23 kg

56. The modern atomic weight scale is based on

(a) O16 (b) C12

(c) H1 (d) C13

57. The percentage weight of Zn in white vitriol [ZnSO4.7H2O]

is approximately equal to (Zn 􀀠 65,S 􀀠 32,O 􀀠 16 and

H = 1)

(a) 33.65 % (b) 32.56 %

(c) 23.65 % (d) 22.65 %

58. The average atomic mass of neon based on following data

is:

Isotope Relative abundance

20Ne 0.9051

21Ne 0.0027

22Ne 0.0922

(a) 0.33 u (b) 20.187 u

(c) 6.729 u (d) 18.058 u

59. What is the average atomic mass of bromine from the

following data : (abundance is in %)

Isotope Mass Abundance

79Br 78.9183361 50.69

81Br 80.916289 49.31

(a) 79.9 (b) 76.6

(c) 75.9 (d) 69.9

60. What is the mass of an atom of oxygen (in gm)?

(a) 2.656 × 10–23 (b) 1.567 × 10–22

(c) 2.0 × 10–22 (d) 3.5 × 10–23

61. If the mass of the one atom is found to be 2.324784×10–23g,

then this atom can be ?

(a) Oxygen (b) Carbon

(c) Fluorine (d) Nitrogen

62. What is the mass of 1 molecule of CO.

(a) 2.325 × 10–23 (b) 4.65 × 10–23

(c) 3.732 × 10–23 (d) 2.895 × 10–23

63. Calculate the volume at STP occupied by 240 gm of SO2.

(a) 64 (b) 84

(c) 59 (d) 73

64. At S.T.P. the density of CCl4 vapours in g/L will be nearest

to:

(a) 6.87 (b) 3.42

(c) 10.26 (d) 4.57

65. The number of gram molecules of oxygen in 6.02 × 1024

CO molecules is

(a) 10 gm molecules (b) 5 gm molecules

(c) 1 gm molecules (d) 0.5 gm molelcules

66. The number of oxygen atoms in 4.4 g of CO2 is

(a) 1.2 × 1023 (b) 6 × 1022

(c) 6 × 1023 (d) 12 × 1023

67. Which has maximum number of molecules?

(a) 7 gm N2 (b) 2 gm H2

(c) 16 gm NO2 (d) 16 gm O2

68. Number of atoms in 558.5 gram Fe (at. wt. of Fe = 55.85

g mol–1) is
(a) twice that in 60 g carbon

(b) 6.023 􀁵 1022

(c) half that in 8 g He

(d) 558.5 􀁵 6.023 􀁵 1023

69. The number of molecules in 16 g of methane is

(a) 3.0 × 1023 (b) 1023

6.02

16 􀁵

(c) 6.023 × 1023 (d) 1023

3.0

16 􀁵

70. Number of g of oxygen in 32.2 g Na2SO4.10 H2O is

(a) 20.8 (b) 2.24

(c) 22.4 (d) 2.08

EBD_7207

SOME BASIC CONCEPTS OF CHEMISTRY 5

71. The number of moles of oxygen in one litre of air containing

21% oxygen by volume, under standard conditions are

(a) 0.0093 mole (b) 0.21 mole

(c) 2.10 mole (d) 0.186 mole

72. The number of molecules in 8.96 litre of a gas at 0ºC and 1

atm. pressure is approximately

(a) 6.023 × 1023 (b) 12.04 × 1023

(c) 18.06 × 1023 (d) 24.08 × 1022

73. The mass of a molecule of water is

(a) 3 × 10–25 kg (b) 3 × 10–26 kg

(c) 1.5 × 10–26 kg (d) 2.5 × 10–26 kg

74. One mole of CO2 contains :

(a) 3 g atoms of CO2

(b) 18.1 × 1023 molecules of CO2

(c) 6.02 × 1023 atoms of O

(d) 6.02 × 1023 atoms of C

75. Volume of a gas at NTP is 1.12 × 10–7cm3. The number of

molecules in it is :

(a) 3.01 × 1012 (b) 3.01 × 1024

(c) 3.01 × 1023 (d) 3.01 × 1020

76. How many atoms are contained in one mole of sucrose

(C12H22O11)?

(a) 20 × 6.02 × 1023 atoms/mol

(b) 45 × 6.02 × 1023 atoms/mol

(c) 5 × 6.02 × 1023 atoms/mol

(d) None of these

77. One litre oxygen gas at S.T.P will weigh :

(a) 1.43 g (b) 2.24 g

(c) 11.2 g (d) 22.4 g

78. Number of moles of NaOH present in 2 litre of 0.5 M NaOH

is :

(a) 1.5 (b) 2.0

(c) 1.0 (d) 2.5

79. O2, N2 are present in the ratio of 1 : 4 by weight. The ratio of

number of molecules is :

(a) 7 : 32 (b) 1 : 4

(c) 2 : 1 (d) 4 : 1

80. How many moles of Al2(SO4)3 would be in 50 g of the

substance ?

(a) 0.083 mole (b) 0.952 mole

(c) 0.481 mole (d) 0.140 mole

81. The mass of 1 mole of electrons is

(a) 9.1 × 10–28g (b) 1.008 mg

(c) 0.55 mg (d) 9.1 × 10–27 g

82. 10 g of hydrogen and 64 g of oxygen were filled in a steel

vessel and exploded. Amount of water produced in this

reaction will be:

(a) 3 mol (b) 4 mol

(c) 1 mol (d) 2 mol

83. Which has the maximum number of molecules among the

following ?

(a) 44 g CO2 (b) 48 g O3

(c) 8 g H2 (d) 64 g SO2

84. The weight of one molecule of a compound C60H122 is

(a) 1.2􀁵10􀀐20 gram (b) 1.4􀁵10􀀐21 gram

(c) 5.025􀁵1023 gram (d) 6.023􀁵1023 gram

85 The simplest formula of a compound containing 50% of

element X (atomic mass 10) and 50% of element Y (atomic

mass 20) is

(a) XY (b) XY3

(c) X2Y (d) X2Y3

86. Empirical formula of hydrocarbon containing 80% carbon

and 20% hydrogen is :

(a) CH3 (b) CH4

(c) CH (d) CH2

87. The empirical formula of a compound is CH2. One mole of

this compound has a mass of 42 grams. Its molecular formula

is :

(a) C3H6 (b) C3H8

(c) CH2 (d) C2H2

88. A compound contains 54.55 % carbon, 9.09% hydrogen ,

36.36% oxygen. The empirical formula of this compound is

(a) C3H5O (b) C4H8O2

(c) C2H4O2 (d) C2H4O

89. In a hydrocarbon, mass ratio of hydrogen and carbon is

1:3, the empirical formula of hydrocarbon is

(a) CH4 (b) CH2

(c) C2H (d) CH3

90. An organic compound contains carbon, hydrogen and

oxygen. Its elemental analysis gave C, 38.71% and H, 9.67%.

The empirical formula of the compound would be :

(a) CH3O (b) CH2O

(c) CHO (d) CH4O

91. A hydrocarbon is composed of 75% carbon. The empirical

formula of the compound is

(a) CH2 (b) CH3

(c) C2H5 (d) CH4

92. 12 gm of Mg (atomic mass 24) will react completely with

hydrochloric acid to give

(a) One mol of H2

(b) 1/2 mol of H2

(c) 2/3 mol of O2

(d) both 1/2 mol of H2 and 1/2 mol of O2

6 SOME BASIC CONCEPTS OF CHEMISTRY

93. 20.0 kg of N2(g) and 3.0 kg of H2(g) are mixed to produce

NH3(g). The amount of NH3(g) formed is

(a) 17 kg (b) 34 kg

(c) 20 kg (d) 3 kg

94. 20.0 kg of H2(g) and 32 kg of O2(g) are reacted to produce

H2O(l). The amount of H2O (l) formed after completion of

reaction is

(a) 62 kg (b) 38 kg

(c) 42 kg (d) 72 kg

95. What is the weight of oxygen required for the complete

combustion of 2.8 kg of ethylene ?

(a) 2.8 kg (b) 6.4 kg

(c) 9.6 kg (d) 96 kg

96. In the reaction

4NH3(g) 􀀎 5O2 (g)􀁯4NO(g) 􀀎 6H2O(l)

When 1 mole of ammonia and 1 mole of O2 are made to react

to completion,

(a) 1.0 mole of H2O is produced

(b) 1.0 mole of NO will be produced

(c) all the oxygen will be consumed

(d) all the ammonia will be consumed

97. What is the molarity of 0.2N Na2CO3 solution?

(a) 0.1 M (b) 0 M

(c) 0.4 M (d) 0.2 M

98. The molar solution of H2SO4 is equal to :

(a) N/2 solution (b) N solution

(c) 2N solution (d) 3N solution

99. Volume of water needed to mix with 10 mL 10N HNO3 to get

0.1 N HNO3 is :

(a) 1000 mL (b) 990 mL

(c) 1010 mL (d) 10 mL

100. One kilogram of a sea water sample contains 6 mg of

dissolved O2. The concentration of O2 in the sample in

ppm is

(a) 0.6 (b) 6.0

(c) 60.0 (d) 16.0

101. A 5 molar solution of H2SO4 is diluted from 1 litre to a

volume of 10 litres, the normality of the solution will be :

(a) 1N (b) 0.1N

(c) 5N (d) 0.5N

102. With increase of temperature, which of these changes?

(a) Molality (b) Weight fraction of solute

(c) Molarity (d) Mole fraction

103. 6.02 × 1020 molecules of urea are present in 100 ml of its

solution. The concentration of urea solution is

(a) 0.02 M (b) 0.01 M

(c) 0.001 M (d) 0.1 M

(Avogadro constant, NA = 6.02 × 1023 mol–1)

104. Two solutions of a substance (non electrolyte) are mixed in

the following manner. 480 ml of 1.5 M first solution + 520 ml

of 1.2 M second solution. What is the molarity of the final

mixture?

(a) 2.70 M (b) 1.344 M

(c) 1.50 M (d) 1.20 M

STATEMENT TYPE QUESTIONS

105. Which of the following statements are correct ?

(i) Both solids and liquids have definite volume.

(ii) Both liquids and gases do not have definite shape.

(iii) Both solids and gases take the shape of the container.

(a) (i) and (iii) (b) (ii) and (iii)

(c) (i) and (ii) (d) (i), (ii) and (iii)

106. Choose correct option based on following statements. Here

T stands for true statement and F for false statement.

(i) Homogeneous mixture has uniform composition

throughout.

(ii) All components of a heterogeneous mixture are

observable to naked eyes.

(iii) All solutions are homogeneous in nature.

(iv) Air is an example of heterogeneous mixture.

(a) TTFF (b) TFTF

(c) FFTT (d) TFFF

107. Read the following and choose the incorrect statements.

(i) Both weight and mass are same quantities used for

measurement of amount of matter present in a

substance

(ii) Mass and weight of a substance vary from one place

to another due to change in gravity.

(iii) SI unit of mass is kilogram and while SI unit of weight

is gram.

(a) (i) and (iii) (b) (ii) and (iii)

(c) (i) and (ii) (d) All of these

108. Moon takes 27.3 days to complete one orbit around the

Earth. Now read the following statements and choose the

correct code. Here T is for true statement and F is for ‘False

statement’.

(i) Moon takes 655.2 hours to complete one orbit around

the Earth.

(ii) Moon takes 39312 seconds to complete one orbit

around the earth.

(iii) Moon takes 1638 minutes to complete one orbit around

the Earth.

(a) F T F (b) T T T

(c) T F F (d) T F T

EBD_7207

SOME BASIC CONCEPTS OF CHEMISTRY 7

109. Give the correct order of initials T or F for following

statements. Use T if statement is true and F if it is false.

(i) Gay-Lussac’s law of gaseous volumes is actually the

law of definite proportion by volume.

(ii) Law of conservation of mass is true for physical

change, but not for chemical change.

(iii) The percentage of oxygen in H2O2 is different from

that in H2O. Hence, it violates law of definite

proportions.

(iv) Fixed mass of A reacts with two different masses of B

(say x and y), then the ratio of x/y can be any positive

integer.
(v) At STP, 5 mL of N2 and H2 have different no. of

molecules.

(a) TTFTF (b) FTTFT

(c) TFFTF (d) TFTTF

110. Consider the following statements.

(i) Atoms of H, O, N and C have identical properties but

different mass.

(ii) Matter is divisible into atoms which are further

indivisible.

(iii) The ratio of N: H in NH3 is 1 : 3 and N : O in nitric oxide

is 2 : 1.

(iv) Dalton’s atomic theory support law of conservation

of mass.

Which of the following pairs of statements is true according

to Dalton’s atomic theory ?

(a) (i) and (ii) (b) (ii) and (iii)

(c) (ii) and (iv) (d) (i) and (iv)

111. Choose the correct option based on following statements.

Here ‘T’ stands for true and ‘F’ stands for false statement.

(i) Molecular mass of cane sugar (C12H22O11) is 182 amu.

(ii) 1 mole of cane sugar contains 6.022 × 1023 molecules

of cane sugar.

(iii) 34.20 g of cane sugar contains 6.022 × 1021 molecules

of cane sugar.

(a) TTF (b) TFT

(c) FTF (d) FTT

MATCHING TYPE QUESTIONS

112. Match the items of Column I, II and III appropriately and

choose the correct option from the codes given below.

Column I Column II Column III

(Multiple) (Prefix) (Symbol)

(A) 10–15 (p) Kilo (i) m

(B) 10–3 (q) yotta (ii) f

(C) 103 (r) milli (iii) k

(D) 1024 (s) femto (iv) Y

(a) A – (s), (ii); B – (r), (i); C – (p), (iii); D – (q), (iv)

(b) A – (p), (ii); B – (q), (iii); C – (r), (i); D – (s), (iv)

(c) A – (q), (iv); B – (p), (ii); C – (p), (i); D – (r), (iii)

(d) A – (r), (iii); B – (p), (ii); C – (s), (i); D – (q), (iv)

113. Match the columns

Column-I Column-II

(Number) (Significant figures)

(A) 29900. (p) 2

(B) 290 (q) 1

(C) 1.23 × 1.331 (r) 4

(D) 20.00 (s) 3

(E) 2.783 – 1 (t) 5

(a) A – (r), B – (q), C – (t), D – (p), E – (s)

(b) A – (t), B – (p), C – (s), D – (r), E – (q)

(c) A – (p), B – (t), C – (s), D – (r), E – (q)

(d) A – (t), B – (s), C – (r), D – (q), E – (p)

114. Match the columns

Column-I Column-II

(Laws of chemical (Scientist)

combinations)

(A) Law of definite (p) Antoine Lavoisier

proportions

(B) Law of multiple (q) Gay Lussac

proportions

(C) Law of conservation (r) Dalton

of mass

(D) Law of gaseous (s) Joseph Proust

volumes

(a) A – (s), B – (r), C – (p), D – (q)

(b) A – (p), B – (r), C – (s), D – (q)

(c) A – (r), B – (p), C – (s), D – (q)

(d) A – (q), B – (s), C – (r), D – (p)

115. Match the columns

Column-I Column-II

(A) C6H5NH2 (p) 84

(B) C6H6 (q) 100

(C) C6H12 (r) 93

(D) CaCO3 (s) 78

(a) A – (p), B – (r), C – (q), D – (s)

(b) A – (r), B – (s), C – (p), D – (q)

(c) A – (r), B – (p), C – (q), D – (s)

(d) A – (r), B – (q), C – (s), D – (p)

116. Match the columns.

Column-I Column-II

(A) 88 g of CO2 (p) 0.25 mol

(B) 6.022 × 1023 molecules (q) 2 mol

of H2O

(C) 5.6 litres of O2 at STP (r) 1 mol

(D) 96 g of O2 (s) 6.022 × 1023 molecules

(E) 1 mol of any gas (t) 3 mol

(a) A – (q), B – (r), C – (p), D – (t), E – (s)

(b) A – (r), B – (q), C – (p), D – (t), E – (s)

(c) A – (q), B – (p), C – (r), D – (t), E – (s)

(d) A – (q), B – (r), C – (p), D – (s), E – (t)

8 SOME BASIC CONCEPTS OF CHEMISTRY

117. Match the mass of elements given in Column I with the

number of moles given in Column II and mark the appropriate

choice. Choose the correct codes formt he options given

below.

Column-I Column-II

(A) 28 g of He (p) 2 moles

(B) 46 g of Na (q) 7 moles

(C) 60 g of Ca (r) 1 mole

(D) 27 g of Al (s) 1.5 mole

(a) A – (s), B – (r), C – (q), D – (p)

(b) A – (p), B – (r), C – (q), D – (s)

(c) A – (r), B – (q), C – (p), D – (s)

(d) A – (q), B – (p), C – (s), D – (r)

118. Match the columns.

Column-I Column-II

(Physical quantity) (Unit)

(A) Molarity (p) mol

(B) Mole fraction (q) Unitless

(C) Mole (r) mol L–1

(D) Molality (s) mol kg–1

(a) A – (r), B – (q), C – (s), D – (p)

(b) A – (r), B – (p), C – (q), D – (s)

(c) A – (r), B – (q), C – (p), D – (s)

(d) A – (q), B – (r), C – (p), D – (s)

ASSERTION-REASON TYPE QUESTIONS

Directions : Each of these questions contain two statements,

Assertion and Reason. Each of these questions also has four

alternative choices, only one of which is the correct answer. You

have to select one of the codes (a), (b), (c) and (d) given below.

(a) Assertion is correct, reason is correct; reason is a correct

explanation for assertion.

(b) Assertion is correct, reason is correct; reason is not a

correct explanation for assertion

(c) Assertion is correct, reason is incorrect

(d) Assertion is incorrect, reason is correct.

119. Assertion : Significant figures for 0.200 is 3 whereas for

200 it is 1.

Reason : Zero at the end or right of a number are significant

provided they are not on the right side of the decimal point.

120. Assertion : 1.231 has three significant figures.

Reason : All numbers right to the decimal point are

significant.

121. Assertion : One atomic mass unit is defined as one twelfth

of the mass of one carbon - 12 atom.

Reason : Carbon-12 isotope is the most abundunt isotope

of carbon and has been chosen as standard.

122. Assertion : Volume of a gas is inversely proportional to the

number of moles of gas.

Reason : The ratio by volume of gaseous reactants and

products is in agreement with their mole ratio.

123. Assertion : Equal moles of different substances contain

same number of constituent particles.

Reason : Equal weights of different substances contain

the same number of constituent particles.

124. Assertion : The empirical mass of ethene is half of its

molecular mass.

Reason : The empirical formula represents the simplest

whole number ratio of various atoms present in a

compound.

CRITICAL THINKING TYPE QUESTIONS

125. What are the significant figure(s) in a broken “ruler”

show below?

0.0 1.0 2.0

(A) 1 (B) 2

(C) 3 (D) 0
(a) A, B and C (b) A, B, D

(c) A only (d) A and B

126. Which one of the following sets of compounds correctly

illustrate the law of reciprocal proportions?

(a) P2O3, PH3, H2O (b) P2O5, PH3, H2O

(c) N2O5, NH3, H2O (d) N2O, NH3, H2O

127. If we consider that 1/6, in place of 1/12, mass of carbon

atom is taken to be the relative atomic mass unit, the mass

of one mole of a substance will

(a) decrease twice

(b) increase two fold

(c) remain unchanged

(d) be a function of the molecular mass of the substance

128. The maximum number of molecules are present in

(a) 15 L of H2 gas at STP (b) 5 L of N2 gas at STP

(c) 0.5 g of H2 gas (d) 10 g of O2 gas

129. How many moles of magnesium phosphate, Mg3(PO4)2 will

contain 0.25 mole of oxygen atoms?

(a) 1.25 × 10–2 (b) 2.5 × 10–2

(c) 0.02 (d) 3.125 × 10–2

130. Volume occupied by one molecule of water

(density = 1 g cm–3) is : ]

(a) 9.0 × 10–23 cm3 (b) 6.023 × 10– 23 cm3

(c) 3.0 × 10–23 cm3 (d) 5.5 × 10– 23 cm3

131. The number of atoms in 0.1 mol of a triatomic gas is :

(NA = 6.02 ×1023 mol–1)

(a) 6.026 × 1022 (b) 1.806 × 1023

(c) 3.600 × 1023 (d) 1.800 × 1022

EBD_7207

SOME BASIC CONCEPTS OF CHEMISTRY 9

132. 1 c.c. N2O at NTP contains :

(a) 10 atoms

224

1.8 􀁵 22

(b) 10 molecules

22400

6.02 􀁵 23

(c) 1023

224

1.32 􀁵 electrons

(d) All of the above

133. How much time (in hours) would it take to distribute one

Avogadro number of wheat grains if 1020 grains are

distributed each second ?

(a) 0.1673 (b) 1.673

(c) 16.73 (d) 167.3

134. Arrange the following in the order of increasing mass (atomic

mass: O = 16, Cu = 63, N = 14)

I. one atom of oxygen

II. one atom of nitrogen

III. 1 × 10–10 mole of oxygen

IV. 1 × 10–10 mole of copper

(a) II < I < III < IV (b) I < II < III < IV

(c) III < II < IV < I (d) IV < II < III < I

135. If 1.5 moles of oxygen combines with Al to form Al2O3,

the mass of Al in g [Atomic mass of Al = 27] used in the

reaction is

(a) 2.7 (b) 54

(c) 40.5 (d) 81

136. Which one of the following is the lightest?

(a) 0.2 mole of hydrogen gas

(b) 6.023 × 1022 molecules of nitrogen

(c) 0.1 g of silver

(d) 0.1 mole of oxygen gas

137. In a compound C, H and N atoms are present in 9 : 1 : 3.5 by

weight. Molecular weight of compound is 108. Molecular

formula of compound is

(a) C2H6N2 (b) C3H4N

(c) C6H8N2 (d) C9H12N3.

138. The empirical formula of an acid is CH2O2, the probable

molecular formula of acid may be :

(a) C3H6O4 (b) CH2O

(c) CH2O2 (d) C2H4O2

139. A gaseous hydrocarbon gives upon combustion 0.72 g of

water and 3.08 g. of CO2. The empirical formula of the

hydrocarbon is :

(a) C2H4 (b) C3H4

(c) C6H5 (d) C7H8

140. Which of the following is the correct empirical and

molecular formulae of a compound, if the molecular mass

of a compound is 80 and compound contains 60% of C,

5% of H and 35% of N ?

(a) C2H2N ; C4H4N2 (b) C3H4N2 ; C6H8N4

(c) C2H4N2 ; C4H8N4 (d) C2H2N ; C2H2N

141. Which of the following is the correct empirical and

molecular formulae of a compound, if the molecular mass

of a compound is 93 and compound containing 77.43% of

C, 7.53% of H and 15.05% of N ?

(a) C3H3

.5N1.5 and C6H7N

(b) C6H7N and C6H7N

(c) C3H3N and C6H7N

(d) C3H3N and C6H6N2

142. Liquid benzene (C6H6) burns in oxygen according to the

equation 2C6H6 (l) 􀀎15O2 (g)􀁿􀁿􀁯12CO2 (g) 􀀎 6H2O(g)

How many litres of O2 at STP are needed to complete the

combustion of 39 g of liquid benzene?(Mol. wt. of O2 = 32,

C6H6 = 78)

(a) 74 L (b) 11.2 L

(c) 22.4 L (d) 84 L

143. Assuming fully decomposed, the volume of CO2 released at

STP on heating 9.85 g of BaCO3 (Atomic mass, Ba = 137)

will be

(a) 2.24 L (b) 4.96 L

(c) 1.12 L (d) 0.84 L

144. The mass of BaCO3 produced when excess CO2 is bubbled

through a solution of 0.205 mol Ba(OH)2 is :

(a) 81 g (b) 40.5 g

(c) 20.25 g (d) 162 g

145. For the reaction Fe2O3 + 3CO2 􀁯 2Fe + 3CO2, the volume

of carbon monoxide required to reduce one mole of ferric

oxide is

(a) 67.2 dm3 (b) 11.2 dm3

(c) 22.4 dm3 (d) 44.8 dm3

146. How many moles of lead (II) chloride will be formed from a

reaction between 6.5 g of PbO and 3.2 g of HCl ?

(a) 0.044 (b) 0.333

(c) 0.011 (d) 0.029

147. Fat is an important source of energy and water, this is

important for the desert animals like camel which store fat

in its hump and provide water and energy. How many

grams and moles of H2O are produced from the

combustion of fat C57H110O6 from 450 gram of fat stored

in hump of camel ?
57 110 6 2 2 2

C H O 163O 57CO 55H O

2 􀀎􀁯 􀀎

(a) 500.56 , 27.80 (b) 450, 26.80

(c) 580, 25.0 (d) 400, 26.6

10 SOME BASIC CONCEPTS OF CHEMISTRY

148. Which of the following option represents correct limiting

reagents in reactions (i), (ii) and (iii) respectively.

(i) C + O2 􀁯 CO2

(26g) (20g)

(ii) N2 + 3H2 􀁯 2NH3

(60g) (80g)

(iii) P4 + 3O2 􀁯 P4O6

(100g) (200g)

(a) C, N2, O2 (b) C, N2, P4

(c) O2, H2, P4 (d) O2, N2, P4

149. 10 mL of 2(M) NaOH solution is added to 200 mL of

0.5 (M) of NaOH solution. What is the final concentration ?

(a) 0.57 (M) (b) 5.7 (M)

(c) 11.4 (M) (d) 1.14 (M)

150. If maximum fluoride ion presence was set to be 4 ppm

number of moles of fluoride in 10 ml drinking water ?

(a) 2.10 × 10–3 (b) 2.10 × 10–2

(c) 3.10 × 10–3 (d) 3.3 × 10–2

151. The increasing order of molarity with 25 gm each of

NaOH, LiOH, Al(OH)3, KOH, B(OH)3 in same volume of

water?

(a) Al(OH)3 < B(OH)3 < KOH < NaOH < LiOH

(b) LiOH < NaOH < KOH < B(OH)3 < Al(OH)3

(c) LiOH < NaOH < B(OH)3 < KOH < Al(OH)3

(d) NaOH < LiOH < B(OH)3 < Al(OH)3 < KOH
EBD_7207