Question
Write note on lead storage cell.
✓
Answer
$\rightarrow $ In consists of a lead anode and a grid of lead packed with lead dioxide $\left( \ce{PbO _2}\right)$ as cathode.
$\rightarrow A 38\%$ solution of sulphuric acid is used as an electrolyte.
$\rightarrow$ The cell reactions when the battery is in use are given below :
Anode : $\ce{Pb ( s )+ SO _4^{2-}( aq ) \rightarrow PbSO _4(s)+2 e ^{-}}$
Cathode : $\ce{PbO _2(s)+ SO _4{ }^{2-}( aq )+4 H ^{+}( aq )+2 e ^{-}}$
$\rightarrow \ce{PbSO _4(s)+2 H _2 O (l)|}$
$\rightarrow$ Overall cell reaction consisting of cathode and anode reactions is :
$ \ce{Pb ( s )+ PbO _2(s)+2 H _2+ SO _4( aq ) \rightarrow 2 PbSO _4(s) +2 H _2 O (l)}$
$\rightarrow$ On charging the battery, the reaction is reversed and $\ce{PbSO _4(s)}$ on the anode and cathode is converted into $Pb$ and $\ce{PbO _2}$, respectively.
$\rightarrow A 38\%$ solution of sulphuric acid is used as an electrolyte.
$\rightarrow$ The cell reactions when the battery is in use are given below :
Anode : $\ce{Pb ( s )+ SO _4^{2-}( aq ) \rightarrow PbSO _4(s)+2 e ^{-}}$
Cathode : $\ce{PbO _2(s)+ SO _4{ }^{2-}( aq )+4 H ^{+}( aq )+2 e ^{-}}$
$\rightarrow \ce{PbSO _4(s)+2 H _2 O (l)|}$
$\rightarrow$ Overall cell reaction consisting of cathode and anode reactions is :
$ \ce{Pb ( s )+ PbO _2(s)+2 H _2+ SO _4( aq ) \rightarrow 2 PbSO _4(s) +2 H _2 O (l)}$
$\rightarrow$ On charging the battery, the reaction is reversed and $\ce{PbSO _4(s)}$ on the anode and cathode is converted into $Pb$ and $\ce{PbO _2}$, respectively.
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