Complete the following using the correct word from those given in the brackets.
A brown precipitate is formed on adding sodium hydroxide to a solution of………...salt. [iron(II)/iron(III)]

Explanation

To solve the question, we need to determine which type of iron salt will produce a brown precipitate when sodium hydroxide (NaOH) is added. We have two options: iron(II) or iron(III).

### Step-by-Step Solution:

1. **Identify the Ions**:
- Iron(II) salt contains Fe²⁺ ions.
- Iron(III) salt contains Fe³⁺ ions.

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