ChemistryPhysical: Electro Chemistry

In lead storage battery, which of the following is the anode reaction?

Answer & explanation

Correct answer: option 3

The lead storage battery is a rechargeable battery. Thus, there are two sets of reaction involved in the lead storage battery

Reaction involved in lead storage battery when it is used are as follow:

Anode:

P b (s) + S O_{4 2 -} (a q) \to P b S O_{4} (s) + 2 e^{-}

Cathode:

P b O_{2} (s) + 4 H^{+} (a q) + S O_{4 2 -} (a q) + 2 e^{-} \to P b S O_{4} (s) + 2 H_{2} O (l)

Thus, overall cell reaction can be given as follow:

P b (s) + P b O_{2} (s) + 4 H^{+} (a q) + 2 S O_{4 2 -} (a q) \to 2 P b S O_{4} (s) + 2 H_{2} O (l)

Reaction involved during the recharging of the battery:

Anode:

P b S O_{4} (s) + 2 H_{2} O (l) \to P b O_{2} (s) + 4 H^{+} (a q) + 2 S O_{4 2 -} (a q) + 2 e^{-}

Cathode:

P b S O_{4} (s) + 2 e^{-} \to P b (s) + S O_{4 2 -} (a q)