Which of the following best describes what the rate law for a reaction shows?

• A. The total amount of products formed at equilibrium
• B. The energy change associated with the reaction
• C. The relationship between the reaction rate and the concentrations of reactants
• D. The mechanism by which the reaction occurs

Answer: (C)

Verified step by step guidance

1. Understand that the rate law expresses how the speed of a chemical reaction depends on the concentrations of the reactants.
2. Recognize that the rate law is typically written in the form \(\text{rate} = k [A]^m [B]^n \ldots\), where \(k\) is the rate constant and \(m\), \(n\) are the reaction orders with respect to each reactant.
3. Note that the rate law does not provide information about the total amount of products formed at equilibrium; that is related to equilibrium constants, not rates.
4. Understand that the rate law does not describe the energy change of the reaction; that is covered by thermodynamics and enthalpy changes.
5. Realize that while the rate law can give clues about the reaction mechanism, it does not directly show the mechanism itself; it specifically relates reaction rate to reactant concentrations.