The general formula of an ester where R represents alkyl group is

Options

A. ROH
B. RCOOH
C. RCOOR
D. RH

Explanation

To determine the general formula of an ester where R represents an alkyl group, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Esters**:
- Esters are organic compounds formed from the reaction of an alcohol and a carboxylic acid. They contain a functional group characterized by a carbonyl (C=O) and an ether (C-O) linkage.

2. **Identifying the General Structure**:
- The general structure of an ester can be represented as R-C(=O)-O-R', where:
- R and R' are alkyl or aryl groups.
- C(=O) indicates the carbonyl group (C double bonded to O).
- O indicates the oxygen atom that connects the carbonyl carbon to the alkyl group.

3. **Formulating the General Formula**:
- The general formula for an ester can be simplified to R-C(=O)-O-R.
- Here, R and R' can be the same or different alkyl groups.

4. **Examples of Esters**:
- If R = CH3 (methyl group) and R' = CH3, the ester is methyl acetate (CH3-C(=O)-O-CH3).
- If R = CH3 and R' = C2H5 (ethyl group), the ester is ethyl acetate (CH3-C(=O)-O-C2H5).

### Final Answer:
The general formula of an ester where R represents an alkyl group is **R-C(=O)-O-R'**.

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