Question

In organic chemistry functional groups, what is the decreasing order of priority among halo- groups, alkyl groups and C=C?

Answer 1

The parent chain is numbered so that the multiple bonds (double and triple bonds) have the lowest numbers, which means, double and triple bonds have priority over alkyl and halo substituents. And, the halo- substituent is considered of equal rank with an alkyl substituent in the numbering of the parent chain. Remember to name them in the lowest numbering possible.