Chemistry | MHT CET 2017 | Discussion Page

Which among the following equations represents in the reduction reaction taking place in lead accumulator at the positive electrode, while it is being used as a source of electrical energy?

$Pb\rightarrow Pb^{2+}$

$Pb^{4+}\rightarrow Pb$

$Pb^{2+}\rightarrow Pb$

$Pb^{4+}\rightarrow Pb^{2+}$

Answer:

Option D

Explanation:

The reaction involved for lead accumulator during discharging i.e, when cell is in the use are

At anode: $Pb(s)+HSO_{4}^{-}(aq)\rightarrow PbSO_{4}(s)+H^{+}+2e^{-}$

At cathode: $PbO_{2}(s)+3H^{+}(aq)+HSO_{4}^{-}(aq)+2e^{-}\rightarrow PbSO_{4}(s)+2H_{2}O(l)$

Overall reaction : $Pb(s)+PbO_{2}(s)+2H^{+}+2HSO_{4}^{-}(aq)\rightarrow 2PbSO_{4}(s)+2H_{2}O(l)$

Discussion Forum

Answer:

Explanation: