Identify the substances that are oxidised and the substance that are reduced in the following reactions.
(i) 4Na(s) + O2(g) → 2Na2O(s)
(ii) CuO(s) + H2(g) → Cu(s) + H2O(l)
(i) 4Na(s) + O2(g) → 2Na2O(s)
In this reaction sodium is oxidised because oxygen combines to sodium form sodium oxide and oxygen is reduced because it is converted into sodium oxide.
(ii) CuO(s) + H2(g) → Cu(s) + H2O(l)
In above reaction, copper oxide is reduced to form copper because copperoxide loses oxygen and form copper where as Hydrogen gets oxidised by gaining oxygen from copper oxide and form water molecule.
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