Ques 3: Identify the substances that are oxidised and the substances that are reduced in the following reactions. (i) 4Na (s) + O2 (g) → 2 Na2O (s) (ii) Cu O (s) + H2 (g) → Cu (s) + H2O (l)

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Ques 3: Identify the substances that are oxidised and the substances that are reduced in the following reactions. 

(i) 4Na (s) + O2 (g) → 2 Na2O (s)

(ii) Cu O (s) + H2 (g) → Cu (s) + H2O (l)


Ans 3: (i). Sodium (Na) is oxidised as it gains oxygen and oxygen gets reduced. 

(ii). Copper oxide (Cu O) is reduced to copper (Cu) while hydrogen (H2) gets oxidised to water (H2O).


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