The temperature above which `Na_(2)SO_(4).10H_(2)O` shows a change in behaviour in the solubility is called……. .

Explanation

To solve the question regarding the temperature above which sodium sulfate decahydrate (Na₂SO₄·10H₂O) shows a change in behavior in solubility, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Compound**: Sodium sulfate decahydrate (Na₂SO₄·10H₂O) is a hydrated salt that contains ten molecules of water of crystallization.

2. **Behavior of Hydrated Salts**: Hydrated salts can exhibit different solubility behaviors at different temperatures. As the temperature increases, the solubility of the salt can change significantly.

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