Iodine Clock Reaction — 2D Kinetics

This is the 2D counterpart to the 3D Iodine Clock Reaction simulator: the same persulfate–iodide clock chemistry, but rendered as a flat animated beaker driven by an explicit 4th-order Runge–Kutta integration of the rate-law ODE system rather than a 3D particle scene. Nothing about the timing is scripted — the moment the solution flips from colorless to blue-black is the actual numerically-found root of the integrated thiosulfate-depletion curve, recomputed live as you change initial concentrations and temperature (via the Arrhenius equation). A concentration-vs-time plot beneath the beaker tracks all four tracked species — iodide, persulfate, thiosulfate and iodine — so you can see the scavenger's depletion line hit zero at the exact instant the beaker's color changes.