Electrophilic addition reaction is easily given by
A) acetylene
B)ethene
C)ethane
D) benzene
Answers
Answer - ( D) Benzene
explanation -
Inspite of the fact that the two -bonds are present in alkynes, these are less reactive than alkenes towards addition reactions (due to symmetrical cylindrical nature of - electron cloud). Further, alkynes do not show geometrical isomerism due to their linear structure
The - electrons of alkynes are more tightly attached to the carbon atoms than -electrons in alkene and hence less easily available for addition reactions with electrophiles. As a result, alkynes are less reactive than alkenes towards electrophilic addition reaction. A majority of addition reactions of alkynes are catalysed by heavy metal ions such as and , etc., while no such catalysts are needed in case of electrophilic addition reactions to alkenes.