Give reasons for the following in one or two sentences.
'Acetic acid can be halogenated in the presence of `P` and `Cl_2`, but formic acid cannot be halogenated in the same way'.

Explanation

To explain why acetic acid can be halogenated in the presence of phosphorus (P) and chlorine (Cl₂), while formic acid cannot, we can break it down into the following steps:

### Step 1: Identify the Structure of Acetic Acid
Acetic acid (CH₃COOH) has a structure that includes a carbon atom (the alpha carbon) adjacent to the carboxylic acid group (COOH). This alpha carbon has three hydrogen atoms attached to it.

### Step 2: Identify the Structure of Formic Acid
Formic acid (HCOOH), on the other hand, has a structure where the carbon atom in the carboxylic acid group is also the only carbon present. Therefore, it does not have an alpha carbon with hydrogen atoms attached.

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