The liquid non-metal is

Options

A. mercury
B. bromine
C. silicon
D. sulphur.

Explanation

To determine the liquid non-metal, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Non-Metals**:
- Non-metals are elements that typically have properties such as a dull surface, poor conductivity of heat and electricity, and can exist in solid or gaseous states.

2. **Identifying Liquid States**:
- Most non-metals are found in solid or gaseous forms. However, we need to identify if there are any exceptions that exist in the liquid state.

3. **Analyzing Common Non-Metals**:
- Common non-metals include elements like carbon, nitrogen, oxygen, sulfur, and phosphorus.
- Among these, we need to check if any are known to be liquid at room temperature.

4. **Identifying Bromine**:
- Bromine (Br) is a non-metal that is unique because it is the only non-metal that exists in a liquid state at room temperature.
- It is important to note that while mercury is also a liquid, it is classified as a metal.

5. **Conclusion**:
- Therefore, the only liquid non-metal is bromine.

### Final Answer:
The liquid non-metal is **Bromine (Br)**.

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