Which equation is used to describe reaction rates?

S products−S reactants

∆H−T∆S

pV=nRT

∆(reactant or product)/∆time

Explanation:

Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.

Rate of reaction can be defined in terms of reactants or products. It is the ratio of disappearance of reactants per unit time or ratio of appearance of products per unit time.

or

gives the entropy change for the reaction.

gives Gibbs free energy.

is the ideal gas equation.

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.