idleHimiya (test)
link: https://www.kongregate.com/games/kbvpneofit/idlehimiya-test
Organic chemistry based. At each minute the timer seems to refresh and work with the formula that you wrote.
Note: very limited game. Only 9 chemical reactions are coded to work, so no "2H2+O2->2H2O", for example.
Also, you need to have "ehough" raw material for it to work. If you have enough and the formula is ok, then the bar below the text input will blink slightly (at least for me, in chrome).