Which of the following does not give white precipitate with ammoniacal `AgNO_3`

Options

A. `CH-=CH`
B. `CH_3-C-=CH`
C. `CH_3-C-=C-CH_3`
D. `undersetunderset(Cl)|CH_2-C-=CH`

Explanation

To determine which of the given options does not give a white precipitate with ammoniacal AgNO₃ (Tollens' reagent), we need to understand the behavior of terminal and non-terminal alkynes with this reagent.

### Step-by-Step Solution:

1. **Understand the Reagent**: Ammoniacal AgNO₃, known as Tollens' reagent, is used to test for terminal alkynes. It reacts with terminal alkynes to produce a white precipitate of silver acetylide.

2. **Identify Terminal and Non-Terminal Alkynes**:
- **Terminal Alkyne**: Has the structure R-C≡C-H, where the triple bond is at the end of the carbon chain. The hydrogen atom attached to the carbon with the triple bond is acidic and can react with Tollens' reagent.
- **Non-Terminal Alkyne**: Has the structure R-C≡C-R', where the triple bond is between two carbon atoms and does not have a hydrogen atom directly bonded to the carbon with the triple bond. Therefore, it does not have an acidic hydrogen.

3. **Analyze Each Option**:
- **Option 1**: Terminal alkyne (R-C≡C-H) → Will give a white precipitate.
- **Option 2**: Terminal alkyne (R-C≡C-H) → Will give a white precipitate.
- **Option 3**: Non-terminal alkyne (R-C≡C-R') → Will NOT give a white precipitate.
- **Option 4**: Terminal alkyne (R-C≡C-H) → Will give a white precipitate.

4. **Conclusion**: Since options 1, 2, and 4 are terminal alkynes, they will give a white precipitate with ammoniacal AgNO₃. Option 3 is a non-terminal alkyne and will not give a white precipitate.

### Final Answer:
**Option 3 does not give a white precipitate with ammoniacal AgNO₃.**