YMMV. Both my daughters did study-abroad programs. My younger daughter fit it in with a double major, interviewed and received offers for several post-junior-year summer jobs, graduated at the top of her class, worked for two years in a highly regarded position for people in her field, and now is in a top-ranked Ph.D. program. I realize, though, that fitting in all the classes might have been more difficult with a major such as chemistry.