A compound soluble in pyridine is:-

1. LiCl

2. CsCl

3. NaCl

4. KCl

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

1. Li, Na

2. Mg, Be

3. Na, K

4. K, Rb

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

1. Na₂CO₃

2. K₂CO₃

3. Cu(OH)₂

4. MgCO₃

The incorrect statement among the following is-

1. Lithium is the strongest reducing agent.

2. Density of potassium is more than sodium.

3. Cs are used in devising photoelectric cells.

4. All alkali metals give a blue solution in liquid ammonia.

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

1. Li⁺(aq)

2. Cs⁺(aq)

3. Li⁺(g) 

4. K⁺(aq)

The suspension of slaked lime in water is known as -

1. Limewater.

2. Quicklime.

3. Milk of lime.

4. Aqueous solution of slaked lime.

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.

An alkaline earth metal sulphate that has hydration enthalpy higher than the lattice enthalpy is -

1. CaSO₄               

2. BeSO₄

3. BaSO₄               

4. SrSO₄

Property of the alkaline earth metals that increases with their atomic number is -

1. Solubility of their hydroxides in water.

2. Solubility of their sulphates in water.

3. Ionisation energy.

4. Electronegativity.

The strongest factor responsible for reducing action of Li metal in an aqueous solution is :

1. Sublimation enthalpy .         

2. Ionisation enthalpy.

3. Hydration enthalpy .             

4. Electron-gain enthalpy.