Craft is going to be your one-stop shop for anything that involves creating an (al)chemical concoction. I wouldn't require any additional rolls to see if the player knows the formula, no more than I'd require a blacksmith to roll Lore to see if she knows the design of a sword.
Lore, with a background or specialty in chemistry, is going to be used to introduce facts, which sounds like something that a "Man of Science" character concept is going to be making lots of use of. "The alchemical run-off from the sorcerer's manse, into this river? It turns out it's incredibly flammable." That kind of stuff.