What is the formulae of
(i) Plaster of Paris (ii) Gypsum ?

Explanation

To determine the formulas of Plaster of Paris and Gypsum, we can follow these steps:

### Step 1: Understand the composition of Gypsum
- Gypsum is a naturally occurring mineral composed of calcium sulfate dihydrate.
- The chemical formula for Gypsum is \( \text{CaSO}_4 \cdot 2\text{H}_2\text{O} \).

### Step 2: Understand the process of making Plaster of Paris
- Plaster of Paris is made by heating Gypsum. When Gypsum is heated to about 120 degrees Celsius, it loses some of its water content.
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