Hydrogenation of benzoyl chloride in the presence of Pd on `BaSO_4` gives

Options

A. a.Benzyl alcohol
B. b.Benzaldehyde
C. c.Benzoic zcid
D. d.Phenol

Explanation

To solve the problem of the hydrogenation of benzoyl chloride in the presence of palladium on barium sulfate (Pd/BaSO4), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactant**:
- The reactant is benzoyl chloride, which has the structure C6H5C(O)Cl. This compound contains a benzene ring (C6H5) attached to a carbonyl group (C=O) and a chlorine atom (Cl).

2. **Understand the Catalyst**:
- The catalyst used is palladium on barium sulfate (Pd/BaSO4), which is known as Lindlar's catalyst. This catalyst is used for selective hydrogenation reactions.

3. **Reaction Mechanism**:
- In the presence of hydrogen (H2) and the Lindlar catalyst, the benzoyl chloride undergoes hydrogenation. The chlorine atom (Cl) is replaced by a hydrogen atom (H).

4. **Formation of the Product**:
- During the hydrogenation process, the carbonyl group (C=O) is reduced to an aldehyde (C=O becomes CHO). Thus, the product formed is benzaldehyde (C6H5CHO).

5. **Conclusion**:
- Therefore, the hydrogenation of benzoyl chloride in the presence of Pd on BaSO4 yields benzaldehyde.

### Final Answer:
The product of the hydrogenation of benzoyl chloride in the presence of palladium on BaSO4 is **benzaldehyde**.