Why is the formation of sulphate in calcination sometimes advantageous ?

Explanation

### Step-by-Step Solution:

1. **Understanding Calcination**: Calcination is a thermal treatment process used to extract metals from their ores. It involves heating the ore in the presence of air or oxygen, which can lead to various chemical reactions.

2. **Formation of Sulfates**: During calcination, certain metal ores can react with sulfur compounds to form metal sulfates. This is particularly common with sulfide ores.

3. **Water Solubility of Sulfates**: One of the key advantages of forming sulfates during calcination is that sulfates are generally soluble in water. This solubility allows for easier extraction of the desired metal.

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