Complete the following reactions :
`CO(g)+H_(2)(g)underset("catalyst")overset(Delta)to`

Explanation

To complete the reaction of carbon monoxide (CO) with hydrogen gas (H₂) in the presence of a catalyst and heat, we follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactants in the reaction are carbon monoxide (CO) and hydrogen gas (H₂).

2. **Determine the Conditions**: The reaction occurs under heat (Δ) and in the presence of a catalyst, which can be zinc oxide (ZnO) or chromium(III) oxide (Cr₂O₃).

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