What happens when:
(i) sodium metal is dropped in water?
(ii) sodium metal is heated in free supply of air?
(iii) sodium peroxide dissolves in water?

Solution

(i) When sodium metal is dropped in water, hydrogen gas is evolved which catches fire.

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(ii) When sodium metal is heated in a free supply of air, sodium peroxide (Na₂O₂) along with small amount of sodium oxide is formed.

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(iii) When sodium peroxide is dissolved in water, hydrogen peroxide is produced.

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