A mixture of methane, ethylene, ethyne gases is passed through a Woulfe's bottle containing ammonical `AgNO_3`. The gas not coming out from bottle is

Options

A. methane
B. ethyne
C. Ethylene
D. all of the above

Answer

To solve the problem, we need to analyze the behavior of the given gases (methane, ethylene, and ethyne) when passed through a Woulfe's bottle containing ammonical AgNO3 (ammonium silver nitrate).

### Step-by-Step Solution:

1. **Identify the Gases**:
- Methane (CH₄) - an alkane
- Ethylene (C₂H₄) - an alkene
- Ethyne (C₂H₂) - an alkyne

2. **Understand the Reaction with Ammonical AgNO3**:
- Ammonical AgNO3 is known to react with alkynes (like ethyne) to form a white precipitate of silver acetylide (AgC≡C) and ammonium nitrate (NH₄NO₃).
- Alkenes (like ethylene) and alkanes (like methane) do not react with ammonical AgNO3.

3. **Determine the Reaction Products**:
- For ethyne (C₂H₂):
\[ \text{C₂H₂} + \text{AgNO₃ (ammonical)} \rightarrow \text{AgC≡C} + \text{NH₄NO₃} \]
- This reaction produces a solid precipitate (AgC≡C), which will not escape from the bottle.

4. **Analyze Each Gas**:
- **Methane (CH₄)**: No reaction with ammonical AgNO3; it will pass through the bottle unreacted.
- **Ethylene (C₂H₄)**: No reaction with ammonical AgNO3; it will also pass through the bottle unreacted.
- **Ethyne (C₂H₂)**: Reacts with ammonical AgNO3, forming a precipitate that will remain in the bottle.

5. **Conclusion**:
- The gas that does not come out of the bottle is the one that reacts and forms a precipitate. Since ethyne reacts and forms a solid, it is the gas that does not come out.
- Therefore, the correct answer is **ethyne (C₂H₂)**.

### Final Answer:
The gas not coming out from the bottle is **ethyne (C₂H₂)**.