During discharging of alead storage battery

Options

A. The reaction at anode is `Pb rarr Pb^(2+)+2e^(-)`
B. The reaction taking place at cathode is
`Pb^(2+)+2e^(-) rarr Pb`
C. The overall reaction is
`Pb+PbO_(2)+4H^(o+) +2SO_(4)^(2-) rarr 2PbSO_(4)+2H_(2)O`
D. The reaction taking place at cathode is
`PbO_(2)+4H^(o+)+2e^(-) rarr Pb^(2+)+2H_(2)O`

Explanation

To solve the question regarding the discharging of a lead storage battery, we will analyze the reactions occurring at the anode and cathode, and then evaluate each of the provided options.

### Step-by-Step Solution:

1. **Identify the Reactions at the Anode and Cathode:**
- **At the Anode (Oxidation):**
- The reaction involves lead (Pb) solid losing electrons to form lead(II) sulfate (PbSO4).
- Reaction:
\[ \text{Pb (s)} + \text{SO}_4^{2-} \rightarrow \text{PbSO}_4 + 2e^- \]

- **At the Cathode (Reduction):**
- The reaction involves lead(IV) oxide (PbO2) gaining electrons and reacting with hydrogen ions (H+) and sulfate ions (SO4^2-) to form lead(II) sulfate (PbSO4) and water (H2O).
- Reaction:
\[ \text{PbO}_2 + 4\text{H}^+ + \text{SO}_4^{2-} + 2e^- \rightarrow \text{PbSO}_4 + 2\text{H}_2\text{O} \]

2. **Determine the Oxidation States:**
- **At the Anode:**
- Lead (Pb) goes from an oxidation state of 0 (in solid form) to +2 (in PbSO4).
- **At the Cathode:**
- Lead (Pb) in PbO2 has an oxidation state of +4 and is reduced to +2 in PbSO4.

3. **Evaluate Each Option:**
- **Option 1:** "The reaction at anode is Pb is converted to Pb2+."
- This is correct, as Pb is indeed oxidized to Pb2+.
- **Option 2:** "The reaction taking place at cathode is Pb2+ gains 2 electrons and converted to Pb."
- This is incorrect; PbO2 (with +4 oxidation state) is reduced, not Pb2+.
- **Option 3:** "Overall reaction is Pb + PbO2 + 4H+ + 2SO4^2- gives 2PbSO4 + 2H2O."
- This is correct, as it represents the net reaction accurately.
- **Option 4:** "The reaction taking place at cathode is PbO2 + 4H+ + 2 electrons gives Pb2+ + 2H2O."
- This is incorrect; the product is PbSO4, not Pb2+.

### Final Summary:
- **Correct Options:** 1 and 3
- **Incorrect Options:** 2 and 4