Meaning, structure and chemical reactions of fuel cells
Answer Text: Fuel cells-Fuel cells are electrochemical cells which convert the chemical energy of a fuel directly to electrical energy. One of the most important fuel cells is thehydrogen oxygen cell.-At the negative terminal, hydrogen reacts with hydroxide ions to form water and electrons are released.2H2(s)+4OH-(aq)→4H2O(l)+4e--At the positive terminal, oxygen and water acquire electrons to form hydroxideions.O2(g)+H2O(l)+4e-→2H2O(l)The overall reaction in the hydrogen/oxygen cell is2H2(g)+O2(g)→2H2O(l)-The cell goes on producing electricity as long as hydrogen and oxygen are fed into it, so that it does not become exhausted like a primary cell. The fuel cell unlike a secondary cell does not store energy.-The electrode other than completing the circuit also catalyses the reactions which increase the output of the cell.