Write a brief note on polymerisation of alkenes.

How many types of polymerisation are possible in alkynes?

State Huckel's rule of aromaticity and explain it interms of cyclopentadiene, cycloxtateraene and cyclopropenylcation.

Among anthracene and cyclopentadiene which is aromatic? Give reason for your answer.

Explain the molecular orbirtal structure of benzene.