1. An electronic device-implemented method for simulating a system that comprises a plurality of chemical reactions, the method comprising: stochastically simulating the system, using the electronic device, by: determining, using the electronic device, a reaction occurrence time for a first chemical reaction using a first probability distribution associated with the first chemical reaction, wherein the first chemical reaction is a non-mass action chemical reaction in which a reaction rate is not proportional to a product of reactant quantities of reactants involved in the non-mass action chemical reaction, and determining, using the electronic device, a reaction time for a second chemical reaction using a second probability distribution associated with the second chemical reaction; and storing the reaction occurrence time for the first chemical reaction and the reaction time for the second chemical reaction in a memory associated with the electronic device.