Chemistry
In an alkaline battery, the anode (negative terminal) is made of zinc powder, which gives more surface area for increased current, and the cathode (positive terminal) is composed of manganese dioxide. The alkaline electrolyte of potassium hydroxide is not consumed during discharge.
The half-reactions are:
- Zn(s) + 2OH−(aq) → ZnO(s) + H2O(l) + 2e−
- 2MnO2(s) + H2O(l) + 2e− → Mn2O3(s) + 2OH−(aq)
Overall reaction:
Read more about this topic: Alkaline Battery
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