Question

1) Which of the following compounds will exhibit cis-trans isomerism?
(IIT JEE 1983)
a) 2-butene
b) 2-butyne
c) 2-butanol
d) butanal​

Answer 1

Answer:

option a is correct answer

Explanation:

The compounds with each doubly bonded carbon attached to two different groups (like Cab=Cab, Cab=Ccd) exhibit geometrical isomerism i.e., cis and trans forms. The geometrical isomerism arises due to restricted rotation of double bond.

However, even though there is restricted rotation for triple bond, alkynes do not exhibit geometrical isomerism, since the triply bonded carbons are attached to one group each only