set 2 MCQ Questions & Answers Detailed Explanation

Question : 1

Consider the following statements regarding Bohr atomic model:

1. It introduces the idea of stationary orbits.
2. It assumes that the angular momentum of the electron is equal to -$(1/2)h/{2π}$
3. It uses the planetary model of the atom involving circular orbits.

a) 1 and 3

b) 1 and 2

c) 2 and 3

d) 1, 2 and 3

Question : 2

Which of the following are values of gas constant R ?

1. 0.0821 L atm k^–1mol^–1
2. 8.21 L torr k^–1mol^–1
3. 82.1 atm mL k^–1mol^–1
4. 8.314 J mol^–1k^–1

a) 1, 2 and 4

b) 1, 2 and 3

c) 1, 3 and 4

d) 2, 3 and 4

Question : 3

Element A belongs to Group VII in p-block and element B belongs to Group I in s-block of the periodic table. Out of the following assumptions, the correct one is :

a) A and B are non-metals

b) A is a metal and B is a non-metal

c) A and B are metals

d) A is a non-metal and B is a metal

Question : 4

Identify the incorrect statements regarding entropy.

1. At absolute zero temperature, entropy of a perfectly crystalline substance is taken to be zero.
2. At absolute zero temperature, the entropy of a perfectly crystalline substance is positive.
3. Absolute entropy of a substance cannot be determined.
4. At 0°C, the entropy of a perfectly crystalline substance is taken to be zero

a) 1, 2 and 4

b) 1, 2 and 3

c) 1, 3 and 4

d) 2, 3 and 4

Question : 5

In an attempt to demonstrate electrical conductivity through an electrolyte, the following apparatus (Fig.) was set up. Which among the following statement(s) is (are) correct?

1. Bulb will not glow because electrolyte is not acidic
2. Bulb will glow because NaOH is a strong base and furnishes ions for conduction.
3. Bulb will not glow because circuit is incomplete
4. Bulb will not glow because it depends upon the type of electrolytic solution

a) 2 only

b) 1 and 3

c) 2 and 4

d) 4 only

Question : 6

The technique of chromatography is used to

a) Determine the structure of substances

b) Dry distillation of colouring substances

c) Identify colour substances

d) Separate the substances from a mixture