Question

question
when numbering the parent chain for a particular straight - chain alkane, on which we find one methyl group and one bromo group, which way will the molecule be numbered?
select the correct answer below:
the way that prioritizes the methyl group (has the ch₃ group occur before the br group on the chain)
the way that prioritizes the bromo group (has the br group occur before the ch₃ group on the chain)
depends on their location on the molecule
it is arbitrary

Explanation:

In naming alkanes with multiple substituents, numbering is done to give the lowest - possible numbers to the substituents overall. So, the numbering depends on the location of the methyl and bromo groups on the molecule to minimize the sum of the locant numbers.

Answer:

C. depends on their location on the molecule