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Question: Lead storage battery has anode and cathode made up of: A. \(Pb\) and \(Pb{O_2}\) B. \(Pb{O_2}\) ...

Lead storage battery has anode and cathode made up of:
A. PbPb and PbO2Pb{O_2}
B. PbO2Pb{O_2} and PbPb
C. Both PbPb
D. Both PbO2Pb{O_2}

Explanation

Solution

Hint: Try to recall that Lead storage batteries are those batteries which are used in our homes Also, they can be charged again by supplying direct current (DC) unlike primary cells which are discarded when they get discharged.

Complete step by step solution:
Lead storage battery, also known as rechargeable battery is an electrochemical cell or group of electrochemical cells that converts chemical energy by reversible chemical reactions and they can be recharged again by-passing direct current through it in the direction opposite to that of its discharge.
They are also known as “accumulators” as they can store energy through reversible chemical reaction.

You should know that Lead storage batteries are also known as Lead-acid batteries. This is the best-known rechargeable battery in which lead electrode,Pb(s)Pb\left( s \right) is used as anode, lead dioxide, PbO2(s)Pb\mathop O\nolimits_2 \left( s \right) is used as cathode and H2SO4(aq)\mathop H\nolimits_2 S\mathop O\nolimits_4 \left( {aq} \right) is used as an electrolyte.
During discharging, when the cell the lead anode is oxidized to lead (II) sulphate, an insoluble substance that adheres to the electrode surface. The two electrons produced per lead atom move through the external circuit to the cathode, where it is reduced to ions in the presence of and form lead (II) sulphate.
The chemical reaction which takes place on both anode and cathode of lead-acid battery are as follows-
Anode- Pb(s)+SO42(aq)PbSO4(s)+2ePb\left( s \right) + \mathop {S\mathop O\nolimits_4 }\nolimits^{2 - } \left( {aq} \right) \to PbS\mathop O\nolimits_4 \left( s \right) + 2\mathop e\nolimits^ - .
Cathode-PbO2(s)+4H+(aq)+SO42(aq)+2ePbSO4(s)+2H2O(l)Pb\mathop O\nolimits_2 \left( s \right) + 4\mathop H\nolimits^ + \left( {aq} \right) + \mathop {S\mathop O\nolimits_4 }\nolimits^{2 - } \left( {aq} \right) + 2\mathop e\nolimits^ - \to PbS\mathop O\nolimits_4 \left( s \right) + 2\mathop H\nolimits_2 O\left( l \right).
And, the overall cell reaction is Pb(s)+PbO2(s)+2H2SO4(aq)2PbSO4(s)+2H2O(l)Pb\left( s \right) + Pb\mathop O\nolimits_2 \left( s \right) + 2\mathop H\nolimits_2 S\mathop O\nolimits_4 \left( {aq} \right) \to 2PbS\mathop O\nolimits_4 \left( s \right) + 2\mathop H\nolimits_2 O\left( l \right).

Hence, from above you can conclude that option A is the correct option to the given question.

Note: It should be remembered that lead-acid batteries are capable of being recharged, which is very important for their use in cars.
Also, during discharging of lead-acid batteries, electrolyte loses much of its dissolved sulphuric acid.