If getting an early job s your only goal then any day it  branch is better than chemical disregarding the institutions you are talking about because chemical industry in india does not ive as many number of jobs in india as the it industry does so focusing only on job IT as a branch is good but yes then you will be leaving  an institute of national importance that is manit and joining an institute that is not widely known just for getting placed I would also tell you that if you work hard at manit  chemical also then also you will get a good placement as manit brand attracts many companies but yes the chemical branch is not so promising as compared ti IT where you will most likely get placed be it in a mass recruiter only so final decision is yours