The IUPAC name of `C_6H_5COCl` :

Options

A. Benzoyl Chloride
B. Benzene chloro ketone
C. Benzene carbonyl chloride
D. Chloro phenyl ketone

Explanation

To determine the IUPAC name of the compound \( C_6H_5COCl \), we can follow these steps:

### Step 1: Identify the Structure
The given molecular formula \( C_6H_5COCl \) indicates that we have a benzene ring (C6H5) attached to a carbonyl group (C=O) and a chlorine atom (Cl).

### Step 2: Determine the Functional Group
In this compound, the functional group is an acid chloride. The presence of the carbonyl group (C=O) bonded to a chlorine atom indicates that it is an acyl chloride.

### Step 3: Name the Parent Compound
The parent compound here is benzene, which is a six-carbon aromatic ring.

### Step 4: Combine the Parent Name with the Functional Group
When naming compounds with acid chlorides, the suffix "carbonyl chloride" is used. Therefore, we combine the name of the benzene ring with the functional group.

### Step 5: Write the IUPAC Name
The IUPAC name for the compound \( C_6H_5COCl \) is "benzene carbonyl chloride".

### Final Answer
The IUPAC name of \( C_6H_5COCl \) is **benzene carbonyl chloride**.

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