Q25 of 39 Page 305

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 ?

(i) When sodium metal is dropped in water, H2 gas is evolved which catches fire due to the exothermicity of the reaction.


2Na (s) + 2H2O (l) → 2NaOH (aq) + H2 (g)


(ii) When sodium metal is heated in free supply of air, sodium peroxide (Na2O2) along with a small amount of sodium oxide (Na2O) is formed.



(iii) When sodium peroxide dissolves in water, sodium hydroxide (NaOH) and hydrogen peroxide (H2O2) is formed.



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