hi,

m.sc in chemistry is two years duration course. In each of the year there will be 2 semesters, do in two years you have to appear in 4 semesters and must have the pass scores in each of the semester. there would be elective subjects in which you would given options to chose any of the subjects. however syllabus may differ college to college and I suggest to follow the syllabus of the university in which you have enrolled for.

hope it would help.