It is because inability of ns² electrons of the valence shell to participate in bonding that

1. Sn²⁺ is reducing while Pb⁴⁺ is oxidising agent

2. Sn²⁺ is oxidising while Pb⁴⁺ is reducing agent

3. Sn²⁺ and Pb²⁺ are both oxidising and reducing agent

4. Sn⁴⁺ is reducing while Pb⁴⁺ is oxidising agent

The number of carbon atoms per unit cell of diamond unit cell is:-

1. 4

2. 8

3. 6

4. 1

Name the type of the structure of silicate in which one oxygen atom of [SiO₄]^4- is

shared?

1. Sheet silicate

2. Pyrosilicate

3. three dimensional silicate

4. Linear chain silicate

Which of the following oxidation states are the most characteristics for lead and tin respectively?

1. +4, +2                     

2. +2, +4

3. +4, +4                     

4. +2, +2

Which one of the following anions is present in chain structure silicates?

(a) ${\mathrm{Si}}_2{\mathrm{O}}_7^{6-}$                 (b) $({\mathrm{Si}}_2{\mathrm{O}}_5^{2-}{)}_{\mathrm{n}}$

(c) $({\mathrm{Si}}_2{\mathrm{O}}_6^{4-}{)}_{\mathrm{n}}$               (d) ${\mathrm{SiO}}_4^{4-}$

AlF₃ is soluble in HF only in the presence of KF due to the formation of:

The correct statement among the following is :

An element that cannot form ${\mathrm{MF}}_6^{3-}$ ion is-

The correct order of atomic radii of the group 13 elements is-

1. B < Al < In < Ga < Tl
2. B < Al < Ga < In < Tl
3. B < Ga < Al < Tl < In
4. B < Ga < Al < In < Tl