Chapter 21, Problem 72A

Interpretation Introduction

Interpretation:

The cis and trans isomer of the following molecule should be drawn:

Concept introduction:

The molecules with same molecular formula and connectivity but differ in spatial arrangements of atoms are said to be geometric isomers of each other.

Answer to Problem 72A

Explanation of Solution

Geometric isomerism, or cis-trans, isomerism is most common in alkenes. The two forms exist due to no free rotation about carbon-carbon double bond. It exists only when the double bonded carbon atoms are joined to two different groups or atoms.

In cis- isomer, the two identical groups or atoms are close to each other whereas in trans- isomer two identical groups or atoms are farther apart.

The structures for cis - and trans - isomers of is: