Question

Which of the following does not show geometrical isomerism?

• A. $C{H}_{3}CCl=CC{H}_{3}Cl$
• B. $CClBr=CBrCl$
• C. $CC{l}_2=CC{l}_2$
• D. (a) and (b) above.

Answer 1

The correct option is C $CC{l}_2=CC{l}_2$

Condition to show geometrical isomerism : $XYC=CXY$
X and Y must have different groups/atoms attached to carbon on the same side of double bond.
Among given compounds, (a) and (b) show geometrical isomerism as they have different groups/atoms attached to carbon on the same side of double bond.
compound c has identical atoms on the same side of double bond; therefore, it can not show cis-trans isomerism.