During charging of lead storage battery, the reaction occurring at the cathode is

Question

During charging of lead storage battery, the reaction occurring at the cathode is (A)  Pb2+ +2e- → Pb  (B)  Pb → Pb2+ + 2e-  (C)  PbSO4 + 2H2O → 2PbO2 +4H+ +SO42- + 2e-  (D)  Pb2+ + SO42- → Pb SO4

Tardigrade Admin · Accepted Answer

(i) Cell reaction during discharge at anode:-

\to

Oxidation reaction at anode[negative electrode]:-

< b r / > P b_{(s)} \to P b_{(a q)}^{2 +} + 2 e^{-} + [oxidation reaction]. < b r / > P b_{(a q)}^{2 +} + S O_{4 (a q)}^{2 -} \to P b S O_{4 (s)} . < b r / > < b r / >

Final Reaction:-

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

[overall oxidation at anode].
(ii) Cell reaction during recharge:-
The reverse of oxidation at anode during discharge is the reduction reaction at cathode during recharging.

< b r / > < b r / > P b_{(a q)}^{2 +} + 2 e^{-} \to P b_{(s)} -^{-} < b r / > P b S O_{4 (s)} \to P b_{(a q)}^{2 +} + S O_{4 (a q)}^{2 -} < b r / > < b r / >

Final Reaction:-

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

Q. During charging of lead storage battery, the reaction occurring at the cathode is

$P b^{2 +} + 2 e^{-} \to P b$

$P b \to P b^{2 +} + 2 e^{-}$

$P b S O_{4} + 2 H_{2} O \to 2 P b O_{2} + 4 H^{+} + S O_{4}^{2 -} + 2 e^{-}$

$P b^{2 +} + S O_{4}^{2 -} \to P b S O_{4}$

Q. During charging of lead storage battery, the reaction occurring at the cathode is

Pb2++2e−→Pb

Pb→Pb2++2e−

PbSO4​+2H2​O→2PbO2​+4H++SO42−​+2e−

Pb2++SO42−​→PbSO4​

$P b^{2 +} + 2 e^{-} \to P b$

$P b \to P b^{2 +} + 2 e^{-}$

$P b S O_{4} + 2 H_{2} O \to 2 P b O_{2} + 4 H^{+} + S O_{4}^{2 -} + 2 e^{-}$

$P b^{2 +} + S O_{4}^{2 -} \to P b S O_{4}$