hi,

see mechanical and chemical engineering is two different streams of engineering, and it has lots of different in full syllabus. basic first year engineering syllabus is quite same in all streams but main subjects starts from second year,mechanical engineering mostly deals with design and priciples of diffrrent machine, air conditioning, large vehicles system design, whether chemical engineering deals with chemical process and methods of operation in different power plants, advantages, management etc. however in India there is less job opportunity for chemical engineering, few opportunities in oil sector, on the other hand there is many opportunities available for mechanical branch , both in private and government.

hope it would help.