Question

a. h — c — cl
|
br
b.
select the correct answer below:
the first molecule (a) contains one chiral carbon, and the second molecule (b) contains four chiral carbons.
neither contains chiral carbons.
the first molecule (a) contains two chiral carbons, and the second molecule (b) contains two chiral carbons.
the first molecule (a) contains no chiral carbons, and the second molecule (b) contains three chiral carbons.

Explanation:

Step1: Determine chiral carbons in (a)

A chiral carbon is a carbon atom that is bonded to four different groups. In molecule (a), the central carbon is bonded to -H, -Cl, -Br, and -CH₃ (assuming the top -CH₃). Since all four groups are different, this carbon is chiral. So molecule (a) has 1 chiral carbon.

Step2: Determine chiral carbons in (b)

In molecule (b), count the carbons bonded to four different groups. The carbon with -Cl and attached to the benzene ring is chiral (attached to -Cl, -benzene, -CH(OH)-, and -H). The carbon with -OH next to it (attached to -OH, -CH(Cl)-benzene, -CH(OH)-, and -H) is chiral. The carbon with -OH further along (attached to -OH, -CH₂CH₃, -CH(OH)-, and -H) is chiral. So molecule (b) has 3 chiral carbons.

Answer:

The first molecule (a) contains one chiral carbon, and the second molecule (b) contains three chiral carbons.