Assertion (A):	When an alkali metal dissolves in liquid NH3 the solution acquires different colors.
Reason (R):	Paired electrons are present in ammonia.

1.	(A) is true and (R) is the correct explanation of (A).
2.	(A) is true but (R) is not the correct explanation of (A).
3.	(A) is true but (R) is false.
4.	Both (A) and (R) are false

Arrange the following ions in increasing order of their mobility in the aqueous solution:

Li⁺, Na⁺, K⁺, Rb⁺ and Cs⁺

$1.<mspace\; width="1em"></mspace>{\mathrm{Li}}^{+}<mspace\; width="1em"></mspace>><mspace\; width="1em"></mspace>{\mathrm{Na}}^{+}<mspace\; width="1em"></mspace>><mspace\; width="1em"></mspace>{\mathrm{K}}^{+}<mspace\; width="1em"></mspace>><mspace\; width="1em"></mspace>{\mathrm{Rb}}^{+}<mspace\; width="1em"></mspace>><mspace\; width="1em"></mspace>{\mathrm{Cs}}^{+}<mspace\; width="1em"></mspace>$
$<mspace\; width="1em"></mspace>2.<mspace\; width="1em"></mspace>{\mathrm{Li}}^{+}<mspace\; width="1em"></mspace><<mspace\; width="1em"></mspace>{\mathrm{Na}}^{+<mspace\; width="1em"></mspace>}<<mspace\; width="1em"></mspace>{\mathrm{K}}^{+}<mspace\; width="1em"></mspace>><mspace\; width="1em"></mspace>{\mathrm{Rb}}^{+}<mspace\; width="1em"></mspace>><mspace\; width="1em"></mspace>{\mathrm{Cs}}^{+}<mspace\; width="1em"></mspace>$
$<mspace\; width="1em"></mspace>3.<mspace\; width="1em"></mspace>{\mathrm{Li}}^{+}<mspace\; width="1em"></mspace><<mspace\; width="1em"></mspace>{\mathrm{Na}}^{+}<mspace\; width="1em"></mspace><<mspace\; width="1em"></mspace>{\mathrm{K}}^{+}<mspace\; width="1em"></mspace><<mspace\; width="1em"></mspace>{\mathrm{Rb}}^{+}<mspace\; width="1em"></mspace><<mspace\; width="1em"></mspace>{\mathrm{Cs}}^{+}<mspace\; width="1em"></mspace>$
$<mspace\; width="1em"></mspace>4.<mspace\; width="1em"></mspace>{\mathrm{Na}}^{+}<mspace\; width="1em"></mspace><<mspace\; width="1em"></mspace>{\mathrm{Li}}^{+}<mspace\; width="1em"></mspace><<mspace\; width="1em"></mspace>{\mathrm{K}}^{+}<mspace\; width="1em"></mspace><<mspace\; width="1em"></mspace>{\mathrm{Cs}}^{+}<mspace\; width="1em"></mspace><<mspace\; width="1em"></mspace>{\mathrm{Rb}}^{+}$

The chemical formula of Plaster of Paris is:

1. ${\mathrm{CaSO}}_4.\frac{1}{2}{\mathrm{H}}_2\mathrm{O}$

2. ${\mathrm{CaSO}}_4.2{\mathrm{H}}_2\mathrm{O}$

3. ${\mathrm{CaSO}}_4.{\mathrm{H}}_2\mathrm{O}$

4. 3CaSO₄.H₂O
$\mathrm{}$

Assertion: BaO is soluble in water but BaSO₄ is insoluble in water.

Reason: Ba²⁺ is a small cation and O^2- is a smaller anion.

1. Assertion is correct and the reason is the correct explanation of assertion.

2. Assertion is correct and the reason is false.

3. Assertion is false and the reason is correct.

4. None of the above

 Alkali metal with the lowest melting point is -

1. Na

2. K

3. Rb

4. Cs

The alkali metal that gives hydrated salts is - 

1. Li

2. Na

3. K

4. Cs

The most stable (thermally) carbonate of alkaline earth metal is-

1. MgCO₃

2. CaCO₃

3. SrCO₃

4. BaCO₃

The increasing order of reactivity among group 1 elements is 

1) Li < Na < K < Rb < Cs

2) Cs < Rb < K < Na < Li

3) Li > Na >K > Na > Cs

4) Cs > Rb > K >Na > Li

The incorrect statement about alkali metals is -

1. They have low density.

2. They have high ionization enthalpy.

3. They are highly reactive.

4. They show photoelectric effect.

The characteristic of alkaline earth metals is that-

1. Their general oxidation state is +1

2. They have a smaller size than alkali metals.

3. They are electronegative in nature.

4. They are strong oxidizing agents.