With increase in temperature solubility of hydrated calcium sulphate

Options

A. Decreases
B. Remains constant
C. Increases
D. Increases initially and then decreases

Answer

To solve the question regarding the effect of temperature on the solubility of hydrated calcium sulfate (CaSO4·xH2O), we can follow these steps:

### Step 1: Understand Hydrated Calcium Sulfate
Hydrated calcium sulfate is represented as CaSO4·xH2O, where "x" indicates the number of water molecules associated with each formula unit of calcium sulfate.

### Step 2: Identify the Nature of the Dissolution Process
When hydrated calcium sulfate dissolves in water, it undergoes a process that can be classified as an exothermic reaction. This means that heat is released when the compound dissolves.

### Step 3: Recall the Effect of Temperature on Exothermic Reactions
For exothermic reactions, increasing the temperature typically leads to a decrease in solubility. This is because, according to Le Chatelier's principle, if the temperature increases, the system will shift to counteract that change by favoring the reactants (in this case, the solid hydrated calcium sulfate) over the products (the dissolved ions).

### Step 4: Conclusion
Based on the exothermic nature of the dissolution of hydrated calcium sulfate, we conclude that as the temperature increases, the solubility of hydrated calcium sulfate decreases.

### Final Answer
With an increase in temperature, the solubility of hydrated calcium sulfate decreases.

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