Question

A mixture of hex-1-yne, hex-2-yne, and hex-3-yne was hydrogenated in the presence of a nickel catalyst until hydrogen uptake ceased. Assuming that the hydrogenation went to completion, how many different six-carbon hydrocarbons were produced

Answer 1

There will be four different six carbon hydrocarbons

Step-by-step explanation:

If we look at the compounds carefully, we will discover that the compounds hex-1-yne and hex-2-yne do not exhibit geometric isomerism. This implies that the two compounds will yield only one six carbon hydrocarbon each if the hydrogenation goes to completion.

However, the hex-3-yne exhibits geometric isomerism and exists as the cis-trans isomers. Each of these isomers of hex-3-yne yields six carbons hydrocarbons upon complete hydrogenation. This brings the total number of six carbon hydrocarbons obtained from the mixture to four.