Question

What happens when:

A Sodium metal is dropped in water

B Sodium metal is heated in free supply of air

C Sodium peroxide dissolves in water

Answer 1

$\text{Reaction of Sodium metal with water}$

When $Na$ metal is dropped in water, it reacts violently to form sodium hydroxide and hydrogen gas. The reaction is highly exothermic, and the evolved gas is hydrogen.

Involved reaction:

$2Na+2H_{2}O\to 2NaOH+H_2+Heat$

$\text{Final answer}:NaOH$ and $H_2$ are formed


$\text{Reaction of sodium metal with heat in presence of air}$

On being heated in air, sodium reacts vigorously with oxygen to form sodium peroxide.

Involved reaction:

$2Na+O_2\to N{a}_2{O}_2$

$\text{Final answer}:N{a}_2{O}_2$ is formed

$\text{Reaction of sodium peroxide}\left(N{a}_2{O}_2\right)\text{with water}:$

When sodium peroxide is dissolved in water, it is readily hydrolysed to form sodium hydroxide and hydrogen peroxide.

Involved reaction follow as:

$2N{a}_2{O}_2\left(s\right)+2H_{2}O\left(l\right)\to 4NaOH\left(aq\right)+H_2{O}_2\left(aq\right)$

$\text{Final answer}:NaOH$ and $H_2{O}_2$ are formed.