Answer:
a) 2-chloro-2,3-dimethylbutane
b) 1-chloro-2,3-dimethylbutane
Explanation:
The monochlorination is a reaction in which we have to add only 1 Cl to the molecule. In this case, we will have to add a Cl to a primary carbon (a) and to a tertiary carbon (b).
In the monochlorination of the primary carbon, we can choose any methyl carbon. For the monochlorination of the terciary carbon we have to choose an CH carbon.
(See the figure)