Which statement is correct?

Options

A. A solution of copper (II) sulphate can be stored in iron vessel.
B. An oxide layer on zinc vessel can be easily removed by washing with dilute `HCl`.
C. Molten `PbBr_(2)` is good conductor of electricity because it contains free ions.
D. in the reaction `Li+(1)/(2)H_(2)toLiH`, hydrogen is a reducing agent.

Explanation

To determine which statement is correct, let's analyze each statement one by one:

### Step 1: Analyze the first statement
**Statement:** A solution of copper(II) sulfate can be stored in an iron vessel.

**Analysis:**
- Copper(II) sulfate (CuSO4) is a salt of copper.
- Iron is more reactive than copper according to the reactivity series.
- If we store copper(II) sulfate in an iron vessel, iron will displace copper from the solution, leading to the formation of iron(II) sulfate (FeSO4) and copper metal.
- Therefore, this statement is **not correct**.

### Step 2: Analyze the second statement
**Statement:** An oxide layer on a zinc vessel can be easily removed by washing with dilute HCl.

**Analysis:**
- Zinc is more reactive than hydrogen.
- When zinc reacts with dilute hydrochloric acid (HCl), it produces zinc chloride (ZnCl2) and hydrogen gas (H2).
- However, the oxide layer on zinc may not be effectively removed just by washing with dilute HCl, as the oxide layer can hinder the reaction.
- Therefore, this statement is also **not correct**.

### Step 3: Analyze the third statement
**Statement:** Molten PbBr2 is a good conductor of electricity because it contains free ions.

**Analysis:**
- In the molten state, PbBr2 dissociates into lead ions (Pb^2+) and bromide ions (Br^-).
- The presence of free-moving ions in the molten state allows it to conduct electricity.
- Therefore, this statement is **correct**.

### Step 4: Analyze the fourth statement
**Statement:** In the reaction Li + 1/2 H2 → LiH, hydrogen is a reducing agent.

**Analysis:**
- In this reaction, lithium (Li) is oxidized, and hydrogen (H2) is reduced.
- The oxidation state of hydrogen changes from 0 in H2 to -1 in LiH, indicating that hydrogen is gaining electrons.
- Therefore, hydrogen acts as an oxidizing agent, not a reducing agent.
- Hence, this statement is **not correct**.

### Conclusion
The only correct statement among the given options is the third one: "Molten PbBr2 is a good conductor of electricity because it contains free ions."

---