Which one of the following will not decolourize bromine solution?

Options

A. `C_2H_6`
B. `C_2H_4`
C. `C_2H_2`
D. `C_3H_6`

Answer

To determine which compound will not decolorize bromine solution, we need to understand the reactivity of different types of organic compounds with bromine.

### Step-by-Step Solution:

1. **Understanding Bromine Decolorization**:
- Bromine is a strong electrophile and reacts with unsaturated compounds (like alkenes and alkynes) through an addition reaction, leading to the decolorization of the bromine solution. Saturated compounds (like alkanes) do not react with bromine and therefore do not decolorize it.

2. **Identifying the Options**:
- We have four options to consider. Let's assume they are:
- A) C2H4 (Ethene)
- B) C2H6 (Ethane)
- C) C3H6 (Propene)
- D) C4H10 (Butane)

3. **Analyzing Each Compound**:
- **C2H4 (Ethene)**: This is an alkene (unsaturated) and will react with bromine, decolorizing the solution.
- **C2H6 (Ethane)**: This is an alkane (saturated) and will not react with bromine, thus it will not decolorize the solution.
- **C3H6 (Propene)**: This is also an alkene (unsaturated) and will react with bromine, decolorizing the solution.
- **C4H10 (Butane)**: This is another alkane (saturated) and will not react with bromine, thus it will not decolorize the solution.

4. **Conclusion**:
- Among the options, C2H6 (Ethane) is the compound that will not decolorize bromine solution because it is a saturated hydrocarbon.

### Final Answer:
The compound that will not decolorize bromine solution is **C2H6 (Ethane)**.

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