A hydrocarbon containing 2 carbon atoms gives Sabatier and Senderens reaction but does not give precipitate with ammoniacal silver nitrate solution. The hydrocarbon in the question is

Options

A. Ethane
B. Acetylene
C. Ethylene
D. None of these

Explanation

To determine the hydrocarbon that meets the criteria given in the question, we will analyze the properties of hydrocarbons with 2 carbon atoms and their reactions.

### Step-by-Step Solution:

1. **Identify the Hydrocarbons with 2 Carbon Atoms**:
The hydrocarbons that contain 2 carbon atoms are:
- Ethane (C2H6)
- Ethylene (C2H4)
- Acetylene (C2H2)

2. **Understand the Sabatier and Senderens Reaction**:
The Sabatier and Senderens reaction involves the hydrogenation of unsaturated hydrocarbons to form saturated hydrocarbons. This means that only unsaturated hydrocarbons (those with double or triple bonds) will react in this process.

3. **Analyze Each Hydrocarbon**:
- **Ethane (C2H6)**:
- Ethane is a saturated hydrocarbon (single bonds only).
- It will not undergo the Sabatier and Senderens reaction because it is already saturated.

- **Ethylene (C2H4)**:
- Ethylene has a double bond (C=C), making it an unsaturated hydrocarbon.
- It can undergo the Sabatier and Senderens reaction to become ethane (C2H6).

- **Acetylene (C2H2)**:
- Acetylene has a triple bond (C≡C), making it also an unsaturated hydrocarbon.
- It can undergo the Sabatier and Senderens reaction to become ethane (C2H6).

4. **Precipitate with Ammoniacal Silver Nitrate**:
The ammoniacal silver nitrate solution is used to test for terminal alkynes (which have a hydrogen atom attached to the carbon of the triple bond).
- **Ethane**: No reaction, as it is saturated.
- **Ethylene**: No reaction, as it does not have acidic hydrogens.
- **Acetylene**: Will give a precipitate because it has acidic hydrogen.

5. **Conclusion**:
The hydrocarbon that gives the Sabatier and Senderens reaction but does not give a precipitate with ammoniacal silver nitrate is **Ethylene (C2H4)**.

### Final Answer:
The hydrocarbon in the question is **Ethylene (C2H4)**.