set 3 MCQ Questions & Answers Detailed Explanation

Question : 1

Which of the following are correct statements?

1. The canonical structures have no real existence
2. Every $AB_5$ molecule does in fact have square pyramidal structure
3. Multiple bonds are always shorter than corresponding single bonds
4. The electron-deficient molecules can act as Lewis acids

a) 2, 3 and 4

b) 1, 2 and 3

c) 1, 3 and 4

d) 1, 2 and 4

Question : 2

Which type of colloidal system is expressed in the fog?

a) Gas in a liquid

b) Solid in a gas

c) Liquid in a gas

d) Liquid in liquid

Question : 3

Consider the following equation for the formation of ammonia from nitrogen and hydrogen:
N₂ + 3H₂ = 2NH₃
How many hydrogen molecules are required to react with 100 molecules of nitrogen?

a) 200

b) 300

c) 100

d) 400

Question : 4

The noble gases are unreactive because

a) they have a full outer shell of electrons

b) they have a half outer shell of neutrons

c) they react with sodium

d) they are too thin

Question : 5

Consider the following statements with reference to the periodic table of chemical elements:

1. Ionisation potential gradually decreases along a period
2. In a group of elements, electron affinity decreases as the atomic weight increases
3. In a given period, electronegativity decreases as the atomic number increases

a) 2 only

b) 1 and 3

c) 1 only

d) 2 and 3

Question : 6

To which block is related an element having electronic configuration 1s²  2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s¹ in the periodic table–

a) p–block

b) d–block

c) s–block

d) f–block