Write the equation for the preparation of polypropylene.

Explanation

To write the equation for the preparation of polypropylene, we will follow these steps:

### Step 1: Identify the Monomer
The monomer used for the preparation of polypropylene is propylene, which has the chemical structure:
\[ \text{C}_3\text{H}_6 \]
This can be represented as:
\[ \text{CH}_2= \text{CH} - \text{CH}_3 \]

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