Which of the following statements is/are correct?

Options

A. Anhydrous `AlCl_3` is used as a catalyst in Friedel-Crafts reaction
B. Iron is used as a catalyst in Haber’s process of manufacturing`NH_3`
C. The oxidation of `SO_2` to`SO_3` requires `V_(2)O_5` as the catalyst
D. The hydrogenation of oil requires nickel as the catalyst

Explanation

To determine which of the statements provided are correct, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement 1: Anhydrous AlCl3 is used as a catalyst in Friedel-Crafts reaction.**
- In Friedel-Crafts reactions, which include alkylation and acylation of aromatic compounds, anhydrous aluminum chloride (AlCl3) acts as a Lewis acid catalyst. It facilitates the formation of the electrophile necessary for the reaction to proceed.
- **Conclusion:** This statement is correct.

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