Acetaldehyde and acetone can be distinguished by

Options

A. `FeCl_3` test
B. `NaHCO_3` test
C. Tollen's test
D. Molisch test

Answer

To distinguish between acetaldehyde and acetone, we can use several tests. Here is a step-by-step solution:

### Step 1: Understanding the Compounds
- **Acetaldehyde (CH₃CHO)** is an aldehyde, while **acetone (CH₃COCH₃)** is a ketone. The functional groups of these compounds are different, which is key to their reactivity.

### Step 2: Performing the Fehling's Test
- **Fehling's Test**: This test is used to distinguish between aldehydes and ketones. Acetaldehyde will reduce Fehling's solution (which contains copper(II) ions) and produce a brick-red precipitate of copper(I) oxide (Cu₂O). Acetone, being a ketone, will not react and will not produce a precipitate.

### Step 3: Performing the Tollen's Test
- **Tollen's Test**: This test uses Tollen's reagent (ammoniacal silver nitrate). Acetaldehyde will reduce Tollen's reagent and produce a silver mirror on the test tube's surface. Acetone, however, will not react, as ketones do not reduce Tollen's reagent.

### Step 4: Performing the NaHCO₃ Test
- **Sodium Bicarbonate Test**: Acetaldehyde can react with sodium bicarbonate to produce carbon dioxide gas, while acetone does not react with NaHCO₃. This can be observed as the evolution of gas bubbles when acetaldehyde is mixed with NaHCO₃.

### Step 5: Performing the Molisch Test
- **Molisch Test**: This test is generally used for detecting the presence of carbohydrates, but it can also indicate the presence of aldehydes. Acetaldehyde will give a positive result, while acetone may not react in the same way.

### Summary of Tests
1. **Fehling's Test**: Positive for acetaldehyde, negative for acetone.
2. **Tollen's Test**: Positive for acetaldehyde (silver mirror), negative for acetone.
3. **NaHCO₃ Test**: Positive for acetaldehyde (bubbles), negative for acetone.
4. **Molisch Test**: Positive for acetaldehyde, variable for acetone.

### Conclusion
By performing these tests, we can effectively distinguish between acetaldehyde and acetone.

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