Select the correct statement for lead storage battery:

Options

A. a) It is a reversible cell
B. b) Salt bridge is not required for lead storage battery
C. c) It is recharged by using DC source of current
D. d) Specific gravity of sulphuric acid solution decreases during discharging

Explanation

To solve the question regarding the correct statements for lead storage batteries, let's analyze each statement step by step.

### Step-by-Step Solution:

1. **Understanding Lead Storage Battery**:
- A lead storage battery, also known as a lead-acid battery, consists of two electrodes: lead (Pb) as the anode and lead dioxide (PbO2) as the cathode, both immersed in a sulfuric acid (H2SO4) electrolyte.

2. **Analyzing the Statements**:
- **Statement 1**: "It is a reversible cell."
- **Explanation**: Lead storage batteries are indeed reversible. They can be discharged to produce electrical energy and recharged to restore their chemical energy. Thus, this statement is **correct**.

- **Statement 2**: "Salt bridge is not required for lead storage battery."
- **Explanation**: In a lead storage battery, both electrodes are immersed in the same electrolyte solution (sulfuric acid), so there is no need for a salt bridge to connect two separate half-cells. Therefore, this statement is **correct**.

- **Statement 3**: "It is recharged by using DC source of current."
- **Explanation**: Lead storage batteries are recharged using a direct current (DC) source. The DC current reverses the chemical reactions that occur during discharge, allowing the battery to be recharged. Hence, this statement is **correct**.

- **Statement 4**: "Specific gravity of the sulfuric acid solution decreases during discharging."
- **Explanation**: During the discharge process, water is formed as a product of the reactions, which dilutes the sulfuric acid solution. As a result, the specific gravity of the sulfuric acid solution decreases. Thus, this statement is **correct**.

3. **Conclusion**:
- All four statements about the lead storage battery are correct.

### Final Answer:
All the statements provided regarding the lead storage battery are correct.

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