In the manufacture of bromine from sea water the mother liquor containing bromide is treated with

Options

A. carbon dioxide
B. chlorine
C. iodine
D. sulphur dioxide

Explanation

To solve the question regarding the manufacture of bromine from seawater, we will follow these steps:

### Step-by-Step Solution:

1. **Understanding the Source of Bromine**:
- Seawater contains bromide ions (Br⁻) in the form of bromides. The process begins with the collection of seawater, which is then concentrated to obtain a mother liquor rich in bromide ions.

2. **Identifying the Reactant**:
- To extract bromine from the bromide ions present in the mother liquor, we need a suitable oxidizing agent. Among the options provided (carbon dioxide, chlorine, iodine, and sulfur dioxide), we need to find which one can oxidize bromide ions.

3. **Choosing the Correct Oxidizing Agent**:
- Chlorine (Cl₂) is a strong oxidizing agent that can oxidize bromide ions (Br⁻) to free bromine (Br₂). The reaction can be represented as:
\[ 2 \text{Br}^- + \text{Cl}_2 \rightarrow 2 \text{Br}_2 + 2 \text{Cl}^- \]
- This shows that chlorine gas reacts with bromide ions to produce bromine and chloride ions.

4. **Conclusion**:
- Therefore, the mother liquor containing bromide is treated with chlorine gas (Cl₂) to manufacture bromine from seawater.

### Final Answer:
The mother liquor containing bromide is treated with **chlorine (Cl₂)**.

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