(Aldol, benzoin, +I, -I, decreases, increases, cyanohydrin, lactic acid, tartaric acid, yellow, white, acetone, penta-3-one, `PCl_(3)`, PCl, benzal chloride, methanol, propanoic acid, ethanol, KOH, KCN, `alpha`-hydrogen atoms, no `alpha`-hydrogens, Cannizzaro's, absence, presence)
When benzaldehyde reacts with ........... it forms ........ and `POCl_(3)`

Explanation

To solve the question regarding the reaction of benzaldehyde with phosphorus pentachloride (PCl5) to form benzyl chloride and phosphoryl chloride (POCl3), we can break it down into the following steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactant in this case is benzaldehyde (C6H5CHO) and phosphorus pentachloride (PCl5).

2. **Understand the Reaction**:
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