Which of the following are functional isomers of methyl ethanoate?

Options

A. `CH_(3)-CH_(2)-COOH`
B.
C. `CH_(3)-O-CH_(2)-oversetoverset(O)(||)(C)-H`
D. `undersetunderset(OH)(|)(CH_(2))-oversetoverset(O)(||)(C)-CH_(3)`

Explanation

To determine which of the given compounds are functional isomers of methyl ethanoate, we need to follow these steps:

### Step 1: Identify the Structure of Methyl Ethanoate
Methyl ethanoate is an ester, and its structure can be represented as:
- **Molecular Formula**: C3H6O2
- **Structural Formula**: CH3COOCH3

This structure consists of a methyl group (CH3) attached to an ethanoate group (C2H3O).

### Step 2: Determine the Functional Groups
Functional isomers have the same molecular formula but different functional groups. The functional groups present in methyl ethanoate are:
- Ester (–COO–)

### Step 3: List Possible Functional Isomers
To find functional isomers, we can consider other functional groups that can be formed with the same molecular formula (C3H6O2). Some possible functional groups include:
- Carboxylic acid (–COOH)
- Aldehyde (–CHO)
- Ketone (–C=O)
- Alcohol (–OH)
- Ether (R–O–R')

### Step 4: Draw Structures for Each Functional Group
1. **Carboxylic Acid**: CH3COOH (Acetic acid)
2. **Aldehyde**: CH3CHO (Acetaldehyde)
3. **Ketone**: CH3C(=O)CH3 (Acetone)
4. **Alcohol**: CH3CH2OH (Ethanol)
5. **Ether**: CH3OCH2CH3 (Dimethyl ether)

### Step 5: Check Molecular Formula
Now, we need to ensure that each of these compounds has the same molecular formula (C3H6O2):
- Methyl ethanoate: C3H6O2
- Acetic acid: C2H4O2 (not isomer)
- Acetaldehyde: C2H4O (not isomer)
- Acetone: C3H6O (not isomer)
- Ethanol: C2H6O (not isomer)
- Dimethyl ether: C3H8O (not isomer)

### Step 6: Identify Functional Isomers
From the above analysis, the functional isomers of methyl ethanoate (C3H6O2) are:
- **Acetic acid** (CH3COOH)
- **Acetaldehyde** (CH3CHO)
- **Ketone** (if we consider propan-2-one, which is not C3H6O2 but is a ketone)
- **Alcohol** (not isomer)
- **Ether** (not isomer)

### Conclusion
The functional isomers of methyl ethanoate are:
- Acetic acid (CH3COOH)
- Acetaldehyde (CH3CHO)