Reaction Kinetics Calculator

The exponential term in the Arrhenius equation is a Boltzmann factor: it estimates the fraction of molecular collisions energetic enough to cross the activation barrier. Because the high-energy tail of the Maxwell-Boltzmann distribution falls exponentially, modest temperature changes can create large rate changes. This is why refrigeration slows spoilage, fevers shift enzyme rates, and high-barrier industrial reactions often need heat or catalysts.

The rate law rate = k·[A]^m tells you how a reaction's speed depends on how much reactant is left. Zero, first, and second order give very different concentration curves: a zero-order reaction consumes reactant at a steady rate until it runs out, while a first-order reaction slows continuously yet keeps a half-life that never changes. Switch the order in this tool and watch the [A]-versus-time curve change shape.

Most reactions slow down as the reactant runs low, but your body clears alcohol at a nearly constant rate — about 0.015 %BAC per hour — regardless of how much you drank. The enzyme alcohol dehydrogenase is fully saturated at ordinary blood-alcohol levels, so it works flat-out, exactly like the zero-order curve in this tool. That is why waiting is the only real cure: doubling the dose doubles the time, not the speed.