Which statements are correct in the case of acetaldehyde and acetone

Options

A. both react with HCN
B. both give iodoform test
C. both react with NaOH to form polymer
D. both can be reduced into alcohols

Answer

To determine which statements are correct regarding acetaldehyde (CH3CHO) and acetone (CH3COCH3), we will analyze each statement step by step.

### Step 1: Reactivity with HCN
Both acetaldehyde and acetone react with hydrogen cyanide (HCN).

- **Acetaldehyde Reaction**: The carbonyl carbon (C=O) in acetaldehyde is attacked by the nucleophile (C≡N) from HCN, leading to the formation of a cyanohydrin.

- **Acetone Reaction**: Similarly, acetone also reacts with HCN in the same manner, forming a cyanohydrin.

**Conclusion**: Both acetaldehyde and acetone react with HCN. This statement is correct.

### Step 2: Iodoform Test
The iodoform test is used to detect the presence of a methyl ketone or an aldehyde with a methyl group adjacent to the carbonyl.

- **Acetaldehyde**: When treated with NaOH in the presence of iodine (I2), acetaldehyde gives a positive iodoform test, producing a yellow precipitate of iodoform (CHI3).

- **Acetone**: Acetone also contains a methyl group adjacent to the carbonyl and will similarly yield a positive iodoform test, producing iodoform.

**Conclusion**: Both acetaldehyde and acetone give a positive iodoform test. This statement is correct.

### Step 3: Reaction with NaOH to Form a Polymer
When aldehydes and ketones react with NaOH, they can undergo aldol condensation, but they do not form polymers.

- **Acetaldehyde**: In the presence of NaOH, acetaldehyde undergoes aldol condensation to form β-hydroxybutyraldehyde, not a polymer.

- **Acetone**: Acetone also undergoes aldol condensation, leading to the formation of a β-hydroxy ketone, but again, no polymer is formed.

**Conclusion**: This statement is incorrect as neither acetaldehyde nor acetone forms a polymer when reacted with NaOH.

### Step 4: Reduction to Alcohol
Both acetaldehyde and acetone can be reduced to alcohols.

- **Acetaldehyde**: When reduced, acetaldehyde yields ethanol (a primary alcohol).

- **Acetone**: When reduced, acetone yields isopropanol (a secondary alcohol).

**Conclusion**: Both compounds can be reduced to alcohols. This statement is correct.

### Final Summary of Statements
1. Both react with HCN - **Correct**
2. Both give the iodoform test - **Correct**
3. Both react with NaOH to form a polymer - **Incorrect**
4. Both can be reduced to alcohol - **Correct**

### Correct Statements
The correct statements regarding acetaldehyde and acetone are 1, 2, and 4.

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