Question
Write note on Hydrogen Oxygen fuel cell.
✓
Answer
→ One of the most successful fuel cells uses the reaction of hydrogen with oxygen to form water
→ In the cell, hydrogen and oxygen are bubbled through porous carbon electrodes into concentrated aqueous sodium hydroxide solution.
→ Catalysts like finely divided platinum or palladium metal are incorporated into the electrodes for increasing the rate of electrode reactions.
→ The electrode reactions are given below :
Cathode : $O _2(g)+2 H _2 O (l)+4 e ^{-} \rightarrow 4 OH ^{-}( aq )$
Anode : $2 H _2(g)+4 OH ^{-}( aq ) \rightarrow 4 H _2 O ( l )+4 e ^{-}$
Net reactions : $2 H _2(g)+ O _2(g) \rightarrow 2 H _2 O (l)$
→ In the cell, hydrogen and oxygen are bubbled through porous carbon electrodes into concentrated aqueous sodium hydroxide solution.
→ Catalysts like finely divided platinum or palladium metal are incorporated into the electrodes for increasing the rate of electrode reactions.
→ The electrode reactions are given below :
Cathode : $O _2(g)+2 H _2 O (l)+4 e ^{-} \rightarrow 4 OH ^{-}( aq )$
Anode : $2 H _2(g)+4 OH ^{-}( aq ) \rightarrow 4 H _2 O ( l )+4 e ^{-}$
Net reactions : $2 H _2(g)+ O _2(g) \rightarrow 2 H _2 O (l)$
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