Which of the following is incorrect ?

A. A storage cell has a reversible chemical reaction
B. A lead-acid cell can be recharged
C. A carbon-zinc cell has unlimited shelf life
D. A primary cell has an irreversible chemical reaction


A. reduces specific gravity of the electrolyte
B. increases specific gravity of the electrolyte
C. produces excessive gassing
D. increases the temperature

Each cell has a vent cap________?

A. to allow gases out when the cell is on charge
B. to add water to the cell if needed
C. to check the level of electrolyte
D. to do all above functions

Capacity of dry cells is_________?

A. more when it is supplying current for intermittent periods
B. more when it is supplying current for continuous periods
C. unaffected by the type of discharge
D. none of the above

It is noticed that durum charging___________?

A. there is a rise in voltage
B. energy is absorbed by the cell
C. specific gravity of H2SO4 is increased
D. the anode becomes chocolate brown in colour (PbCfe) and cathode becomes grey metallic lead (Pb)
E. all of the above

Over charging______________?

A. produces excessive gassing
B. loosens the active material
C. increases the temperature resulting in buckling of plates
D. all above