What product forms when an alkene undergoes hydrogenation?

What product forms when an alkene undergoes hydrogenation?

• A. An alkane.
• B. A diol.
• C. An alkynes.
• D. A carboxylic acid.

Answer: (A)

Hydrogenation adds hydrogen across a carbon–carbon double bond, converting the C=C into a single bond and giving a saturated hydrocarbon. So an alkene reacts with H2 under metal catalyst to form an alkane. The other options would require introducing oxygen (a diol), forming a triple bond (an alkyne) or oxidizing to a carboxylic acid, none of which come from simple hydrogenation of an alkene. Therefore, the product is an alkane.

Hydrogenation adds hydrogen across a carbon–carbon double bond, converting the C=C into a single bond and giving a saturated hydrocarbon. So an alkene reacts with H2 under metal catalyst to form an alkane. The other options would require introducing oxygen (a diol), forming a triple bond (an alkyne) or oxidizing to a carboxylic acid, none of which come from simple hydrogenation of an alkene. Therefore, the product is an alkane.