# What is the longest carbon chain in this molecule?

##### 1 Answer

Jul 24, 2017

I got

**5-bromo-3-chlorooctane**.

#### Explanation:

It is sure that you got parent chain 8 ie. correct.

But according to lowest set of locant rule,

the side group which gives lowest locant will be preferred until and unless a functional group is not present.

Now

*Counting from left*

Location of Br = 4.

Location of Cl = 5.

So the sum of locations of Cl and Br is = 4+5 = 9.

*counting from right*

Location of Cl = 3

Location of Br = 5

So the sum of locations of Cl and Br is = 3+5 = 8.

Since we get lowest locant set on counting from right therefore the correct IUPAC name, maintaining the alphabetical order of prefix name, would be:

**5-bromo-3-chlorooctane**.