Le Chat

squeeze it, heat it, feed it — it undoes whatever you did.

squeeze the vessel, drag the heat, tap the vial — every disturbance gets partly undone, live, not just in the final number

The Haber process makes ammonia from nitrogen and hydrogen, and the reaction runs both ways at once, forward and backward, at equal speed once it settles. Le Chatelier's principle says that if you disturb that balance -- more pressure, more heat, more of one ingredient -- the system shifts to partly cancel what you did, never fully. Squeeze it and it makes fewer molecules to relieve the pressure. Heat it and it eats the extra heat by running backwards, which is why the industrial condition is a compromise rather than the extreme of either dial. This single trade-off, tuned by hand a century ago, is what feeds a meaningful fraction of the planet.

Concepts: chemistry, thermodynamics.

An interactive you play with one thumb, on Wundr.