Galvanic cells are classified into primary and secondary cells.(a) Wri

1.	Galvanic cells are classified into primary and secondary cells.(a) Write any two differences between primary cell and secondary cell.(b) (i) What is a fuel cell?(ii) Write the overall cell reaction in H2 – O2 fuel cell.
Answer» (a) Primary cell Cell reaction cannot be reversed and hence can not be recharged, cannot be reused again. e.g. Dry cell, Mercury cell Secondary cell Cell reaction can be reversed and hence can be recharged, can be resued again. e.g. Lead storage battery, nickel-cadmium cell (b) (i) Fuel cell is a galvanic cell that is designed to convert the energy of combustion of fuels directly into electncal energy. (ii) 2H₂(g) + O₂(g) → 2H₂O(l)

Galvanic cells are classified into primary and secondary cells.(a) Write any two differences between primary cell and secondary cell.(b) (i) What is a fuel cell?(ii) Write the overall cell reaction in H2 – O2 fuel cell.

Answer»

(a) Primary cell

Cell reaction cannot be reversed and hence can not be recharged, cannot be reused again. e.g. Dry cell, Mercury cell

Secondary cell

Cell reaction can be reversed and hence can be recharged, can be resued again. e.g. Lead storage battery, nickel-cadmium cell

(b) (i) Fuel cell is a galvanic cell that is designed to convert the energy of combustion of fuels directly into electncal energy.

(ii) 2H₂(g) + O₂(g) → 2H₂O(l)

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