One day Kamal saw that her mother was roasting peanuts in it pen (kadahi) in the kitchen and she had taken ordinary salt to roast the peanuts. She was surprised to observe that in spite of very high temperature, the salt does not melt and the peanuts also get roasted.
Common salt is used as a raw material in the preparation of washing soda in which the number of molecules of water of crystallisation is:

Options

A. 10
B. 7
C. 5
D. 2

Explanation

To solve the question regarding the number of molecules of water of crystallization in washing soda, we can follow these steps:

### Step 1: Understand the Composition of Washing Soda
Washing soda is chemically known as sodium carbonate. Its chemical formula is Na2CO3.

### Step 2: Identify the Hydrated Form of Washing Soda
Washing soda is often found in a hydrated form, which means it contains water molecules in its crystal structure. The common hydrated form of washing soda is sodium carbonate decahydrate.

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