Common table salt becomes moist and does not pour easily in rainy season because:

1. It contains magnesium chloride.

2. It contains magnesium carbonate.

3. It melts slightly in rainy season.

4. Sodium chloride is hygroscopic.

A  mixture of Al(OH)₃ and Fe(OH)₃ can be separated easily by treating it with:

1. HCl

2. NH₄OH

3. HNO₃

4. NaOH

Alkali metals are characterised by:

1. Good conductors of heat and electricity.

2. High melting points.

3. Low oxidation potentials.

4. High ionisation potentials.

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

Which has lowest thermal stability?

1. Li₂CO₃

2. Na₂CO₃

3. K₂CO₃

4. Rb₂CO₃

An alkali metal that reacts with nitrogen to form nitride is -

1. Li

2. Na

3. Cs

4. None of the above.

Caustic soda is:

1. Efflorescent

2. Deliquescent

3. Hygroscopic

4. Oxidant

The most basic oxide among the following is:

1. Na₂O

2. BaO

3. As₂O₃

4. Al₂O₃

Pearl ash and caustic potash are chemically:

1. K₂CO₃ and KOH

2. KOH and K₂CO₃

3. Na₂CO₃ and KOH

4. Na₂CO₃ and NaOH

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

1. Zn

2. Fe

3. K

4. Al