The value of the rate constant k for a given reaction changes when
- A. the concentration of the reactants is increased
- B. the volume of the vessel is changed
- C. the temperature is changed
- D. more product is removed
Explanation
The rate constant is constant only at a fixed temperature; the Arrhenius equation shows it rising sharply as temperature increases or as activation energy falls, which is also why a catalyst increases k. Changing concentration changes the rate but leaves k untouched, since the concentration term is already written separately in the rate equation. This distinction between rate and rate constant is examined frequently.