For 10 points, name this measure of the speed of a reaction.
One constant involved in this quantity can be calculated from the temperature using the Eyring equation, or by an equation including a steric factor. The temperature and activation energy are also used to calculate this quantity. One way of calculating it, the Arrhenius equation, is based on the collision model. In zero order reactions, it is determined only by a constant, and not by the concentration of the reactants. It can be calculated by laws that have first and second order varieties. For 10 points, name this measure of the speed of a reaction.
One constant involved in this quantity can be calculated from the temperature using the Eyring equation, or by an equation including a steric factor.
reaction {rate} [or {rate} constant; accept word equivalents]