Dissolving metallic Zn in excess of NaOH produces:-

(1) Na₂ZnO₂

(2) Zn(OH)₂

(3) ZnO

(4) Zn(OH)₂ & Na₂ZnO₂

 Superoxide is formed on heating with an excess of air by:-

1. Li, Na

2. Mg, Be

3. Na, K

4. K, Rb

On heating Li₂CO₃ and Na₂CO₃.10H₂O, residue is left after heating. The weight loss is due to

1. Evolution of CO₂ from Na₂CO₃.10H₂O only

2. Evolution of CO₂ from Li₂CO₃ only

3. Due to evolution of CO₂ from Li₂CO₃ and H₂O from Na₂CO₃.10H₂O 

4. H₂O from  Na₂CO₃.10H₂O 

A colourless salt among the following that gives violet colour to Bunsen flame is -

1. Na₂CO₃

2. K₂CO₃

3. Cu(OH)₂

4. MgCO₃

An ion among the following that have largest size in an aqueous solution is -

1. Rb⁺

2. Na⁺

3. K⁺

4. Li⁺

Which of the following alkali metal ion in aqueous solution is the best conductor of electricity?

(1) Li⁺

(2) Na⁺

(3) Cs⁺

(4) K⁺

Which salt will not impart color to flame?

1. LiCl

2. MgCl₂

3. CaCl₂

4. KI

An ion that has the largest size among the following is :

1. Li⁺(aq)

2. Cs⁺(aq)

3. Li⁺(g) 

4. K⁺(aq)

Ionic mobility of which of the following alkali metal ions is lowest when an aqueous solution of their salts are put under an electric field?

(1) Na                       

(2) K

(3) Rb                       

(4) Li

The incorrect statement among the following regarding Beryllium is-

1. It is rendered passive by nitric acid.

2. lt forms Be₂C

3. It's salts rarely hydrolyze.

4. It's hydride is electron-deficient and polymeric.