The compound gives a sooty flame on burning .

Options

A. `CH_(4)`
B. `C_(3)H_(3)`
C. `C_(2)H_(6) `
D. `C_(2)H_(4)`

Explanation

To determine which compound gives a sooty flame upon burning, we need to analyze the options provided: CH₄ (methane), C₂H₃ (ethyne), C₂H₆ (ethane), and C₂H₄ (ethylene).

### Step-by-Step Solution:

1. **Understanding Sooty Flame**:
- A sooty flame is produced during the incomplete combustion of hydrocarbons. This occurs when there is a higher ratio of carbon to hydrogen in the compound, leading to the formation of carbon particles (soot) instead of complete combustion products like carbon dioxide (CO₂).

2. **Analyzing the Compounds**:
- **CH₄ (Methane)**: This is a saturated hydrocarbon with a high hydrogen-to-carbon ratio. It burns completely to produce CO₂ and H₂O, resulting in a clean flame.
- **C₂H₃ (Ethyne)**: This is an unsaturated hydrocarbon (alkyne) and has a higher carbon content relative to hydrogen. It can produce a sooty flame due to incomplete combustion.
- **C₂H₆ (Ethane)**: This is also a saturated hydrocarbon. Similar to methane, it has a high hydrogen-to-carbon ratio and burns completely, producing a clean flame.
- **C₂H₄ (Ethylene)**: This is an unsaturated hydrocarbon (alkene) and has a higher carbon content compared to hydrogen. It is likely to undergo incomplete combustion, leading to a sooty flame.

3. **Conclusion**:
- Among the given options, C₂H₄ (ethylene) is the compound that will produce a sooty flame upon burning due to its unsaturated nature and the likelihood of incomplete combustion.

### Final Answer:
The compound that gives a sooty flame on burning is **C₂H₄ (Ethylene)**.