I need to draw a complete expanded structure of the alkane whose name is 1-chloro-2,3-dimethylpentane?

Question

Then, I have to circle two chiral carbons.
I know how 1-chloro-2,3-dimethylpentane
structure looks like but I don't know how to expanded.

Answer 1

Chiral carbons will be those carbons that have something different attached to each of the 4 bonding sites. In your problem, that would be the 2 and 3 carbons.

Draw the normal structure for the alkane. For the chiral isomers the methyls will be up or down. You have 4 possible combinations. Up-Up, Up-Down, Down-Up and Down-Down.

Answer 2

To expand the structure, just draw all the places where the lines meet as carbons (put a C there).

Then fill in as many Hs as needed to make 4 bonds for each C.

A chiral carbon will have 4 different things bound to it.