Halogenation of alkanes

Exercise 3

         

A non-cyclic alkane with molar mass $M = 72 \frac {g}{mol} $ has four isomers, two of these are enantiomers. Find the molecular formula!

$C_nH_{2n+2}$ $M=72$ $12n+2n+2=72$ $n=5$ $C_5H_{12}$

Represent the enantiomer $ S $ in perspective!

Give one of the most stable conformations of this enantiomer in Newmann projection!