The correct explanation for the lower atomic radius of Ga as compared to Al is -

1. Poor shielding effect of the 2d-electrons

2. Poor shielding effect of the 3d-electrons

3. Poor shielding effect of the 3p-electrons

4. Poor shielding effect of the 2s-electrons

Amphoteric oxides are:

1. Tl₂O₃, SiO₂

2. ${\mathrm{CO}}_2$, ${\mathrm{B}}_2{\mathrm{O}}_3$

3. ${\mathrm{B}}_2{\mathrm{O}}_3$, ${\mathrm{SiO}}_2$

4. Al₂O₃ , PbO₂

An aqueous solution of Borax is-

Boric acid is polymeric due to-

1. Its acidic nature.

2. The presence of hydrogen bonds.

3. Its monobasic nature.

4. Its geometry.

The hybridization of boron in diborane is-

1. sp

2. s${\mathrm{p}}^2$

3. s${\mathrm{p}}^3$

4. ds${\mathrm{p}}^2$

Thermodynamically the most stable form of carbon is-

The incorrect statement among the given options is :

The incorrect statement regarding allotropes/allotropy is :

The correct statement(s) regarding thallium is/are :

1. Thallium displays both +1, and +3 oxidation states.

2. It resembles group 1 metals in some reactions.

3. Thallium only shows a +1 oxidation state.

4. Both (1) and (2) 

Which statement among the following is incorrect?