Q44 of 65 Page 24

The following reaction takes place when aluminium powder is heated with MnO2


(a) Is aluminium getting reduced?


(b) Is MnO2 getting oxidised?

(a) No, aluminium is getting oxidized as oxygen is added to it to form aluminium oxide.


(b) No, manganese is getting reduced as it has lost its oxygen.


Since aluminium is more reactive than manganese, it displaces manganese from its oxide. Aluminum accepts oxygen from manganese dioxide. It reduces the manganese dioxide to manganese and aluminum oxide is formed.


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