Hi student, Comparison between mechanical engineering and Chemical engineering is like comparison between apples and oranges. These two are completely different branches. In mechanical engineering, you need to have good knowledge of mechanics and some concepts of physics too. Whereas Chemical engineering is all about chemistry. So choosing between these two branches should be completely based on your interests. Unless you like to study something, its worthless to take it up. About comparison between nit trichy and iit madras, one has the benefit of being iit. But that alone does not make it a good choice. Because the branch that you get in a particular college matters a lot. So according to me you should choose the college depending upon the branch that you prefer. Because ultimately you have to study yourself, the faculty in colleges are almost same and in the end what matters is your own hard work.

Hope it helps.

Good luck.