Is there a defined concept of chemistry in Openclonk?
If not, I would suggest to have a look into alchemy.
There would be many benefits from assuming that alchemical science is proven to be fundamentally right.
For example: A concept of magic (transmutation etc...) could be implemented without leaving the world of steampunk.
Handling chemical production would be much easier and much more interesting at the same time.
The basis materials for all alchemical processes are already implemented except for quicksilver and salt.
Once the logic of the concept is explained in a scenario, the player can easily explore everything by himself through analogies, which could provide an explanation for implementing riddles into the game

I could provide scientifical knowledge about all aspects of the matter, if you happen to be interested.