Question

Why do dry cells not last forever?

Answer 1

Dry Cells

1. It is a type of portable battery, commonly used for portable electrical devices.
2. Dry cells are not rechargeable.
3. The dry cell shown in the figure is made up of $\mathrm{Zinc}$ as anode, $\mathrm{Graphite}\mathrm{Rod}$ as cathode and the Chemical inside it is a paste of ${\mathrm{MnO}}_2$,${\mathrm{NH}}_4\mathrm{Cl}$ and $\mathrm{Carbon}$
4. A dry cell is a device which generates electricity from chemical reactions. When two electrodes are connected in closed path electrons flow through them thus causing the flow of electricity.
5. They are made up of a fixed amount of reacting chemicals, which get exhausted on use.

Thus dry cells do not last forever.