mass action like rate law for second order irreversible reactions, one reactant, one essential stimulator mass action like rate law for second order irreversible reactions, one reactant, one essential stimulator, discrete scheme Reaction scheme where the products are created from a reactant and the change of a product quantity is proportional to the product of the reactant and the stimulator quantities. The reaction scheme does not include any reverse process that creates the reactant from the products. The change of a product quantity is proportional to the quantity of the reactant and the stimulator. It is to be used in a reaction modelled using a discrete framework. <n0:math xmlns:n0="http://www.w3.org/1998/Math/MathML"> <n2:semantics xmlns:n2="http://biomodels.net/SBO/" definitionURL="http://biomodels.net/SBO/#SBO:0000063"> <n2:lambda> <n2:bvar><n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000067">c</n2:ci></n2:bvar> <n2:bvar><n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000508">R</n2:ci></n2:bvar> <n2:bvar><n2:ci definitionURL="http://biomodels.net/SBO/#SBO:0000523">A</n2:ci></n2:bvar> <n2:apply> <n2:times /> <n2:ci>c</n2:ci> <n2:ci>R</n2:ci> <n2:ci>A</n2:ci> </n2:apply> </n2:lambda> </n2:semantics> </n0:math>