Concept:A molecule is chiral if it contains at least one carbon atom bonded to four different groups.
Explanation:Check each option for a chiral centre.
A. 2-Bromopropane:
CH3​−CHBr−CH3​ — the central carbon has two identical
CH3​ groups. Not chiral.
B. 2-Bromo-2-methylbutane: the central carbon is attached to two identical
CH3​ groups. Not chiral.
C. 2-Bromo-3-methylbutane:
CH3​−CHBr−CH(CH3​)−CH3​. The carbon bearing bromine is attached to
H,
Br,
CH3​, and
CH(CH3​)2​. All four groups are different. Hence, it is chiral.
D. 3-Bromopentane:
CH3​CH2​−CHBr−CH2​CH3​ — the central carbon has two identical ethyl groups. Not chiral.
Answer:The chiral molecule is
2-Bromo-
3-methylbutane, which is Option C.
