Propanal is the functional isomer of

Options

A. propane
B. propan-1-ol
C. propan-2-ol
D. propan-2-one.

Explanation

To determine the functional isomer of propanal, we need to follow these steps:

### Step 1: Identify the Molecular Formula of Propanal
Propanal is an aldehyde with the molecular formula C3H6O.

### Step 2: Understand the Concept of Functional Isomers
Functional isomers are compounds that have the same molecular formula but differ in their functional groups. This means we need to find another compound that has the same molecular formula (C3H6O) but a different functional group.

### Step 3: List Possible Compounds with the Same Molecular Formula
We need to find compounds that have the molecular formula C3H6O. Some possible candidates include:
- Propan-1-ol (an alcohol)
- Propan-2-ol (an alcohol)
- Acetone (a ketone)

### Step 4: Identify Functional Groups
- Propanal (C3H6O) has an aldehyde functional group.
- Propan-1-ol (C3H8O) and Propan-2-ol (C3H8O) have alcohol functional groups.
- Acetone (C3H6O) has a ketone functional group.

### Step 5: Compare Functional Groups
Among the compounds listed:
- Propanal (aldehyde) and Acetone (ketone) both have the same molecular formula C3H6O but differ in their functional groups.

### Conclusion
The functional isomer of propanal is acetone.

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