Right now the only “chemicals” in the game seem to be:
bleach
ammonia
What are some other chemicals we could add for various actual recipes?
saltpeter (process into nitric acid, add ammonia, get ammonium nitrate for fertilizer or basic explosives, add fuel oil (we can say gasoline maybe) to get quality explosives; ammonium nitrate can also be used in crystal meth recipes)
chlorine (either to make bleach or to make chlorine tablets which can purify water, or possibly for chemical weapons, like the teargas grenades)
lye (from ashes, either for cooking/cure foods, or make soap, or possibly again as a chemical weapon)
maybe we could do a little more with the poppy plants; in theory you should be able to make a lot of different actual painkillers from them, not just “poppy sleep” and “poppy painkiller.”
it could be cool to need a whole lab setup, and to find various specific and realistic chemicals around, which the player couldn’t recognize without sufficient cooking skill.