Give the reaction for preparing benzene.

Explanation

To prepare benzene from ethyne (acetylene), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactant**: We start with ethyne (C₂H₂), which is also known as acetylene. The molecular formula for ethyne is CH≡CH.

2. **Use of Multiple Ethyne Molecules**: To prepare benzene, we need three molecules of ethyne. Therefore, we will write the reaction using three ethyne molecules:
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