Benzoyl chloride is prepared from benzoic acid by :

Options

A. `Cl_2,hv`
B. `SO_2,Cl_2`
C. `SOCl_2`
D. `Cl_2,H_2O`

Answer

To prepare benzoyl chloride from benzoic acid, we can follow these steps:

### Step 1: Identify the Reactants
We start with benzoic acid (C6H5COOH) as our reactant.

### Step 2: Choose the Reagent
To convert benzoic acid to benzoyl chloride, we need to use thionyl chloride (SOCl2) as the reagent. Thionyl chloride is commonly used to convert carboxylic acids into their corresponding acid chlorides.

### Step 3: Write the Reaction
The reaction can be represented as follows:

\[ \text{C}_6\text{H}_5\text{COOH} + \text{SOCl}_2 \rightarrow \text{C}_6\text{H}_5\text{COCl} + \text{SO}_2 + \text{HCl} \]

Here, benzoic acid reacts with thionyl chloride to produce benzoyl chloride (C6H5COCl), sulfur dioxide (SO2), and hydrochloric acid (HCl).

### Step 4: Conclusion
From the above reaction, we can conclude that benzoyl chloride is prepared from benzoic acid by treating it with thionyl chloride (SOCl2).

### Final Answer
Thus, the correct option is C.

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