Hello Swati,
Just as B.Sc, you cannot opt a particular topic or a subject in chemistry to do a Master's degree (M.Sc). You will have to study chemistry generally which means that you have to study physical, inorganic as well as organic chemistry all together. Just that the degree is higher and so the subject will be explored more deeply.
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile