Sodium reacts with water less vigorously than potassium because:

1. it has higher atomic weight

2. it is less electropositive

3. it is more electronegative

4. it is metal

Excess of dilute sodium hydroxide solution is gradually added with shaking to an aqueous solution of zinc sulphate. What would you observe?

1. A light blue precipitate is first formed which finally dissolves to give a deep blue solution

2. A white precipitate appears which dissolves to give a colourless solution.

3. A white precipitation is formed which does not dissolve 

4. No change takes place and the solution remains clear

The most dangerous method of precipitating hydrogen would be by the action of HCl on:

1. Zn

2. Fe

3. K

4. Al

The products of the electrolysis of aqueous solution of common salt are:

1. Na + Cl₂

2. H₂ + O₂

3. NaOH + H₂ + Cl₂

4. NaOH + Cl₂ + O₂

KO₂ is used in oxygen cylinder in space air craft and submarines because it:

1. absorbs CO₂ and increase O₂ content

2. eliminate moisture

3. absorbs CO₂

4. produces O₂

Which one is the highest melting point halide?

1. NaCl

2. NaBr

3. NaF

4. NaI

Manufacture of NaOH is done by:

1. Castner - Kellner process

2. Solvay process

3. Brine process

4. Mond's process

Lithium is the only alkali metal which is not placed in kerosene but is wrapped in paraffin wax, because:

1. it reacts with kerosene

2. it floats to the surface of kerosene because of low density

3. it does not react with air and H₂O

4. none of the above

The element which does not dissolve in caustic soda is:

1. silicon

2. aluminium

3. zinc

4. cadmium

Sodium metal cannot be stored under:

1. benzene

2. kerosene

3. alcohol

4. toluene