Write the hydrogenation reactions of ethene

Explanation

To write the hydrogenation reaction of ethene, we will follow these steps:

### Step 1: Identify the reactants
The reactant in this reaction is ethene, which has the chemical formula C2H4. Ethene has a double bond between the two carbon atoms.

### Step 2: Write the hydrogen molecule
The hydrogen molecule is represented as H2. This molecule will react with ethene in the hydrogenation process.

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