Question

How many stereoisomers does this molecule have?
$C{H}_{3}CH=CHC{H}_{2}CHBrC{H}_3$

• A. $8$
• B. $2$
• C. $4$
• D. $6$

Answer 1

The correct option is C $4$

The given compound may be written as

Both geometrical isomerism (cis-trans form) and optical isomerism is possible in the given compound.
Number of optical isomer $=2^n=2^1=2$
(where n = number of asymmetric carbon)
Hence total number of stereoisomers $=2+2=4$.