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Write the chemistry of recharging the lead storage battery, highlighting all the materials that are involved during recharging.
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A lead storage battery consists of anode of lead, cathode of a grid of lead packed with lead dioxide \(\left(\mathrm{PbO}_2\right)\) and \(38 \%\) \(\mathrm{H}_2 \mathrm{SO}_4\) solution as electrolyte. When the battery is in use, the reaction taking place are :
Anode : \(\mathrm{Pb}(s)+\mathrm{SO}_4{ }^{2-}(a q) \rightarrow \mathrm{PbSO}_4(s)+2 \mathrm{e}^{-}\)
Cathode : \(\mathrm{PbO}_2(s)+\mathrm{SO}_4^{2-}(a q)+4 \mathrm{H}^{+}(a q)+2 \mathrm{e}^{-}\)
\(\rightarrow \mathrm{PbSO}_4(s)+2 \mathrm{H}_2 \mathrm{O}(l)\)
Overall Reaction: \(\mathrm{Pb}(s)+\mathrm{PbO}_2(s)+2 \mathrm{H}_2 \mathrm{SO}_4(a q)\)
\(\rightarrow 2 \mathrm{PbSO}_4(s)+2 \mathrm{H}_2 \mathrm{O}(l)\)
On charging the battery, the reverse reaction takes place, i.e., \(\mathrm{PbSO}_4\) deposited on electrodes is converted back to \(\mathrm{Pb}\) and \(\mathrm{PbO}_2\) and \(\mathrm{H}_2 \mathrm{SO}_4\) is regenerated.
Anode : \(\mathrm{Pb}(s)+\mathrm{SO}_4{ }^{2-}(a q) \rightarrow \mathrm{PbSO}_4(s)+2 \mathrm{e}^{-}\)
Cathode : \(\mathrm{PbO}_2(s)+\mathrm{SO}_4^{2-}(a q)+4 \mathrm{H}^{+}(a q)+2 \mathrm{e}^{-}\)
\(\rightarrow \mathrm{PbSO}_4(s)+2 \mathrm{H}_2 \mathrm{O}(l)\)
Overall Reaction: \(\mathrm{Pb}(s)+\mathrm{PbO}_2(s)+2 \mathrm{H}_2 \mathrm{SO}_4(a q)\)
\(\rightarrow 2 \mathrm{PbSO}_4(s)+2 \mathrm{H}_2 \mathrm{O}(l)\)
On charging the battery, the reverse reaction takes place, i.e., \(\mathrm{PbSO}_4\) deposited on electrodes is converted back to \(\mathrm{Pb}\) and \(\mathrm{PbO}_2\) and \(\mathrm{H}_2 \mathrm{SO}_4\) is regenerated.
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