Ester formation involves the reaction of

Options

A. an aldehyde and a ketone
B. an alcohol with RMgX
C. two molecules of an acid with dehydrating agent
D. an acyl halide with an alcohol.

Answer

To answer the question "Ester formation involves the reaction of," we can follow these steps:

### Step 1: Identify the reactants involved in ester formation.
Ester formation primarily involves the reaction between an acid (or acyl halide) and an alcohol.

### Step 2: Understand the reaction mechanism.
The general reaction for ester formation can be represented as:
- **Acid (or acyl halide) + Alcohol → Ester + Water**

### Step 3: Recognize the specific reactants.
In this case, we can specify that the acid can be an acyl halide (like acetyl chloride) and the alcohol can be any simple alcohol (like ethanol).

### Step 4: Write the reaction equation.
For example, if we take acetic acid (an acid) and ethanol (an alcohol), the reaction can be written as:
- **CH₃COOH + C₂H₅OH → CH₃COOC₂H₅ + H₂O**

### Step 5: Conclusion.
From the options provided, the correct answer is that ester formation involves the reaction of acid halides (or acyl halides) with alcohol.

### Final Answer:
Ester formation involves the reaction of acid halides (or acyl halides) with alcohol.

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