Silver mirror is a test for `:`

Options

A. Aldehydes
B. Thio alcohols
C. Amines
D. Ethers

Answer

**Step-by-Step Solution:**

1. **Understanding the Silver Mirror Test:**
The silver mirror test is a qualitative test used to distinguish between aldehydes and ketones. It is specifically used to identify the presence of aldehydes.

2. **Reagents Used:**
The reagent used in this test is ammonical silver nitrate, which has the formula Ag(NH3)2NO3. This reagent contains silver ions that can be reduced.

3. **Reaction Mechanism:**
When an aldehyde is present, it acts as a reducing agent. The aldehyde is oxidized to a carboxylic acid, while the silver ions in the ammonical silver nitrate are reduced to metallic silver.

4. **Formation of Silver Mirror:**
As the reaction proceeds, metallic silver is deposited on the inner surface of the test tube, forming a shiny silver mirror. This is a positive indication for the presence of an aldehyde.

5. **Distinguishing Aldehydes from Ketones:**
Ketones do not react with ammonical silver nitrate under the same conditions and therefore do not produce a silver mirror. This is the key difference that allows the test to distinguish between these two functional groups.

6. **Conclusion:**
The silver mirror test is a specific test for aldehydes, as they give a positive result by forming a silver mirror, while ketones do not react and thus give a negative result.

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