BITSAT Chemistry Some Basic Concepts Of Chemistry MCQs

Question: If a 25.0 mL sample of sulfuric acid is titrated with 50.0 mL of 0.025 M sodium hydroxide to a phenolphthalein endpoint, what is the molarity of the acid?

a) 0.020 M

b) 0.100 M

c) 0.025 M

d) 0.050 M

Answer: 0.025 M

Question: Find which of the following compound can have mass ratios of C:H:O as 6:1:24

a) HO-(C=O)-OH

b) HO-(C=O)-H

c) H-(C=O)-H

d) H₃CO-(C=O)-H

Answer: HO-(C=O)-OH

Question: The normality of 26% (wt/vol) solution of ammonia (density = 0.855 ) is approximately :

a) 1.5

b) 0.4

c) 15.3

d) 4

Answer: 15.3

Question: 1.25 g of a sample of Na₂CO₃ and Na₂SO₄ is dissolved in 250 ml solution. 25 ml of this solution neutralises 20 ml of 0.1N H2SO4.The % of Na₂CO₃ in this sample is

a) 84.8%

b) 8.48%

c) 15.2%

d) 42.4%

Answer: 84.8%

Question: A compound of Xe and F is found to have 53.5% of Xe. What is oxidation number of Xe in this compound ?

a) – 4

b) 0

c) + 4

d) + 6

Answer: + 6

Question: The prefix 10¹⁸ is

a) giga

b) kilo

c) exa

d) nano

Answer: exa

Question: The formation of CO and CO₂ illustrates the law of

a) Reciprocal proportion

b) Conservation of mass

c) Multiple proportion

d) Constant composition

Answer: Multiple proportion

Question: The number of atoms in 0.004 gm of magnesium is close to

a) 24 

b) 2 × 10²⁰

c) 10²⁰

d) 6.02 × 10²³

Answer: 10²⁰

Question: How many grams of concentrated nitric acid solution should be used to prepare 250 mL of 2.0M HNO₃? The concentrated acid is 70% HNO₃

a) 90.0 g conc. HNO₃ 

b) 70.0 g conc. HNO₃

c) 54.0 g conc. HNO₃

d) 45.0 g conc. HNO₃

Answer: 45.0 g conc. HNO₃

Question: Number of atoms of He in 100 amu of He (atomic wt. of He is 4) are :

a) 25

b) 100

c) 50

d) 100 × 6 × 10^–23

Answer: 25

Question: The product of atomic weight and specific heat of any element is a constant, approximately 6.4. This is known as

a) Dalton’s law

b) Avogadro’s law

c) Newton’s law

d) Dulong Pettit law

Answer: Dulong Pettit law

Question: 1.520 g of hydroxide of a metal on ignition gave 0.995g of oxide. The equivalent weight of metal is :

a) 1.52

b) 0.995

c) 190

d) 9

Answer: 9

Question: The vapour density of ozone is

a) 16

b) 32

c) 24

d) 48

Answer: 24

Question: In redox reaction 1 gm-eq of reducing agent requires P gm-eq. of oxidising agent. The value of P is

a) 1

b) 2

c) 3

d) Depends on reaction

Answer: 1

Question: Given the numbers : 161 cm, 0.161 cm, 0.0161 cm. The number of significant figures for the three numbers are

a) 3, 4 and 5 respectively

b) 3, 3 and 4 respectively

c) 3, 3 and 3 respectively

d) 3, 4 and 4 respectively

Answer: 3, 3 and 3 respectively

Question: In which of the following number all zeros are significant?

a) 0.0005

b) 0.0500

c) 50.000

d) 0.0050

Answer: 50.000

Question: The number of electrons in a mole of hydrogen molecule is

a) 6.023 × 10²³

b) 12.046 × 10²³

c) 3.0115 × 10²³

d) Indefinite

Answer: 12.046 × 10²³

Question: When 30 liters of H₂ and 30 liters of N₂ are reacted NH₃ is formed and the yield is only 50%.The composition of the gaseous mixture will be

a) 5L of N₂, 5L of H₂ and 5 L of NH₃

b) 5L of N₂, 10L of H₂ and 10 L of NH₃.

c) 10L of N₂, 15L of H₂ and 5 L of NH₃

d) 5L of N₂, 15L of H₂ and 10 L of NH₃

Answer: 5L of N₂, 15L of H₂ and 10 L of NH₃

Question: The equivalent weight of H₂O₂ in is

a) 17

b) 34

c) 68

d) 85

Answer: 17

Question: A gas is found to have a formula [CO]_x. Its vapour density is 70, the x is :

a) 3.0

b) 3.5

c) 5.0

d) 6.5

Answer: 5.0

Question: The volume of Cl₂ at STP obtained on reacting 4.35 g MnO₂ with conc. HCl (At. wt. of Mn = 55)

a) 4.48 litre

b) 2.24 litres

c) 1.12 litre

d) 0.56 litre

Answer: 1.12 litre

Question: The number of sodium atoms in 2 moles of sodium ferrocyanide is :

a) 12 × 10²³ 

b) 26 × 10²³

c) 34 × 10²³

d) 48 × 10²³

Answer: 48 × 10²³

Question: 1.520 g of hydroxide of a metal on ignition gave 0.995g of oxide. The equivalent weight of metal is :

a) 1.52

b) 0.995

c) 190

d) 9

Answer: 9

Question: The product of atomic weight and specific heat of any element is a constant, approximately 6.4. This is known as

a) Dalton’s law

b) Avogadro’s law

c) Newton’s law

d) Dulong Pettit law

Answer: Dulong Pettit law

Question: Number of atoms of He in 100 amu of He (atomic wt. of He is 4) are :

a) 25

b) 100

c) 50

d) 100 × 6 × 10^–23

Answer: 25