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Question: What happens when the lead storage battery is discharged? A. \(S{O_2}\) is evolved B. Lead sulph...

What happens when the lead storage battery is discharged?
A. SO2S{O_2} is evolved
B. Lead sulphate is consumed
C. Lead is formed
D. H2SO4{H_2}S{O_4} is consumed

Explanation

Solution

We know that lead storage batteries are secondary voltaic cells that can easily be recharged. The reaction that takes place inside the cell takes place during the recharging process is equal to the reverse of the reactions during the process of discharge. The process of discharging the stored energy relies on different positive and negative plates.

Complete step by step answer:
As we know that the lead storage battery is a secondary voltaic cell that can be recharged. The reactions that take place during the recharging process are just the opposite of the reactions taking place during the discharge. During discharge, the chemical energy gets converted into electrical energy. During recharging, electrical energy gets converted into chemical energy.
We know that the anode is made from a series of lead plates with spongy lead. Also, the anode is a negative electrode. The cathode is also a series of lead plates that is coated with lead dioxide. And cathode is a positive electrode. Here, the aqueous sulfuric acid solution is the electrolyte in the reaction.
2H2SO4(aq)→4H+(aq)+2SO42−(aq)2{H_2}S{O_4}(aq) \to 4{H^ + }(aq) + 2S{O_4}^{2 - }(aq)
During this discharge, the following reactions take place. Where sulfuric acid gets ionized to give protons and sulphate ions. At the anode, lead reacts with sulphate ions to form lead sulphate and two electrons.
Pb(s)+SO42−(aq)→PbSO4(s)+2e−(anode)Pb(s) + S{O_4}^{2 - }(aq) \to PbS{O_4}(s) + 2{e^ - }(anode)
At the cathode, lead dioxide reacts with protons and sulphate ions then it forms lead sulphate and water.
PbO2(s)+4H+(aq)+SO42−(aq)+2e−→PbSO4(s)+H2O(l)Pb{O_2}(s) + 4{H^ + }(aq) + S{O_4}^{2 - }(aq) + 2{e^ - } \to PbS{O_4}(s) + {H_2}O(l)
Now, the overall cell reaction is the reaction that takes place between lead, lead dioxide, and sulfuric acid to form lead sulphate and water.
Pb(s)+PbO2(s)+2H2SO4(aq)→2PbSO4(s)+2H2O(l)Pb(s) + Pb{O_2}(s) + 2{H_2}S{O_4}(aq) \to 2PbS{O_4}(s) + 2{H_2}O(l)
Therefore, we can conclude that when the lead storage battery is discharged then sulfuric acid is consumed.
Hence, the correct answer is Option D.

Note:
The sulfuric acid consumed in the reaction is used in the production of fertilizers, e.g., superphosphate of lime and ammonium sulphate. It is widely used in the manufacture of chemicals, like hydrochloric acid, nitric acid, sulphate salts, synthetic detergents, dyes and pigments, explosives, and drugs. It is a highly corrosive chemical that is potentially explosive in its concentrated form. Also, it can cause severe skin burns and irritation in the nose and throat. Also, causes difficulties in breathing if inhaled.