see i dont recommend madras for northern ppl only due to cultural shock...now iits have one distinct principle...that once ppl cum in they r treated equals...like all departments are equal...placements entirely depend on what u have done in 4 years and to alesser extent on department..and in terms of monetary chemical has heaviest placement due to oil and gas paying heavily...chemical course is not abt chemistry also...its different...and the scope of chem engg is vast..so i wud say go for chem bombay
a 2nd year IIT DELHI student, doing B.Tech in chemical engineering