I didn't get a look at the workout; it took me to some work from home page. But if you're dead set on a 5 day split, one group each day (which I tend to recommend against) then go Chest, Back, Legs, Shoulders, Arms. See, everyone wants big arms and devotes an entire day to them. Not only are the bi's and tri's a secondary mover on almost all upper body movements, they're also a tiny muscle group. They don't need their own day. If you're going to do one muscle group per day try Chest with 1 tricep exercise at the end, then back with one bicep exercise at the end, then legs, then shoulders. Instead of the arms day, do an abs/core strength day.