Question

Write a chemical equation to represent what happens when hydrogen gas is passed through an unsaturated hydrocarbon in the presence of nickel acting as a catalyst

Answer 1

Any unsaturated compound reacts with hydrogen in the presence of a catalyst such as nickel or palladium to form a saturated compound. This reaction is called HYDROGENATION.
In the above example, ethene reacts with hydrogen in the presence of nickel to form ethane.

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