Final answer:
The product formed when hydrogen reacts with 3-methyl-2-butanone is a secondary alcohol due to the reduction of the ketone group to a hydroxyl group.
Step-by-step explanation:
When hydrogen is reacted with 3-methyl-2-butanone, the product formed is a secondary alcohol. This is due to the fact that the reduction of a ketone forms a secondary alcohol. With reference to the 3-methyl-2-butanone structure, the carbonyl group (C=O) is located on the second carbon atom, which is attached to two other carbon atoms. Upon reaction with hydrogen (typically in the presence of a catalyst such as nickel or platinum), the ketone is reduced, and the oxygen atom in the C=O group is replaced with a hydroxyl group (OH), creating a molecule where the OH group is on a carbon that is bonded to two other carbons, characteristic of a secondary alcohol.