Question

Which of the followings represents a cis form?

• A.
• B.
• C.
• D.

Answer 1

The correct option is C

Cis-trans configurations:
In cycloalkanes, when same groups present at the same side it is of cis form and if same group present at the different side then it is of trans form.

In (a), both methyl are in opposite direction so it is a trans isomer.

In (b), both methyl are in opposite direction so it is a trans isomer.

In (c), both methyl are in same direction so it is a cis isomer.

In (d), both methyl in same carbon and have same groups at the terminal of carbon carbon single bond. Hence, this does not show geometrical isomerism.