Fuel cells are special types of galvanic cells. (a) (i) Whataregalvan

1.	Fuel cells are special types of galvanic cells. (a) (i) Whataregalvaniccells?(ii) Write any two advantages of fuel cells.(b) Write the electrode reactions is H2 – O2 fuel cells.
Answer» (a) (i) These are devices for converting chemical energy into electrical energy. The decrease in free energy in a spontaneous chemical process appears as electrical energy. e.g., Daniell oeil. (ii) (1) Fuel cells are pollution free. (2) Fuel cells are highly efficient (about 70%) compared to thermal plants (about 40%) (3) Fuel cells run continuously as long as the reactants are supplied. (b) At cathode: O₂(g) + 2H₂O(l) + 4e → 4OH(aq) At anode: 2H₂(g) + 4OH(aq) → 4H₂O(l)

Fuel cells are special types of galvanic cells. (a) (i) Whataregalvaniccells?(ii) Write any two advantages of fuel cells.(b) Write the electrode reactions is H2 – O2 fuel cells.

Answer»

(a) (i) These are devices for converting chemical energy into electrical energy. The decrease in free energy in a spontaneous chemical process appears as electrical energy. e.g., Daniell oeil.
(ii) (1) Fuel cells are pollution free.

(2) Fuel cells are highly efficient (about 70%) compared to thermal plants (about 40%)

(3) Fuel cells run continuously as long as the reactants are supplied.

(b) At cathode:

O₂(g) + 2H₂O(l) + 4e → 4OH(aq)

At anode:

2H₂(g) + 4OH(aq) → 4H₂O(l)

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