Give reason in one two sentence for the following ''The hydroxide of aluminum and iron are insoluble in water. However, NaOH is used to separate one from other .''

Explanation

### Step-by-Step Solution:

1. **Understanding the Solubility of Hydroxides**: Both aluminum hydroxide (Al(OH)₃) and iron(III) hydroxide (Fe(OH)₃) are insoluble in water. This means that when mixed with water, they do not dissolve and remain as solid precipitates.

2. **Role of Sodium Hydroxide (NaOH)**: When sodium hydroxide (NaOH) is added to a mixture of aluminum and iron hydroxides, a chemical reaction occurs specifically with aluminum hydroxide.

3. **Reaction of Aluminum Hydroxide with NaOH**: Aluminum hydroxide reacts with NaOH to form sodium meta-aluminate (NaAlO₂), which is soluble in water. The reaction can be represented as:
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