Question

define hydrogenation

Answer 1

Hydrogenation – meaning, to treat with hydrogen – is a chemical reaction between molecular hydrogen and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. ... Hydrogenation reduces double and triple bonds in hydrocarbons. 

Answer 2

combine chemically an unsaturated compound with hydrogen. Liquid vegetable oils are often hydrogenated to turn them into solids. To turn coal into oil by combining its carbon with hydrogen to form hydrocarbons.
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