It depends upon you which course you are interested in as one is a masters course in chemistry whereas other is an engineering course in ece so you will have to decide whether you want to do engineering or a msc msc takes 5 years where as btech ece takes 4 years to get completed msc chemistry course is more oriented towards research in chemistry where as ece relates with electronics so decide which course you want to pursue also don't take msc just for nit tag take it only if it interests you if interested in btech then ece at iiitsricity is better option