if i have to decide between bits pilani chem & bits goa/hyderababd eee, which one is better with 319 bitsat marks

I think Bits Pilani chemical would be the better choice. Chemical is a good branch, i am pursuing chemical engineering itself and its scope is too good in the future. Also, Bits pilani would provide you good exposure.
THanks

In my opinion you should go for eee in goa/heydrabad, because eee is evergreen stream.