With the help of an example, explain the process of hydrogenation.
Mention the essential conditions for the reaction and state the change in physical property with the formation of the product.

Explanation

### Step-by-Step Solution:

**Step 1: Define Hydrogenation**
Hydrogenation is a chemical reaction that involves the addition of hydrogen (H₂) to unsaturated hydrocarbons, such as alkenes or alkynes, to convert them into saturated hydrocarbons.

**Step 2: Provide an Example**
A common example of hydrogenation is the conversion of vegetable oil (which contains unsaturated fats) into ghee (which contains saturated fats). In this process, the double bonds in the unsaturated fatty acids of vegetable oil are broken and hydrogen is added, resulting in the formation of saturated fats.

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