The Arrhenius equation shows that the rate constant increases when
Correct answer: C. the activation energy decreases or the temperature rises
- A. the activation energy increases
- B. the temperature falls
- C. the activation energy decreases or the temperature rises
- D. the concentration of reactants rises
Explanation
The equation contains an exponential term in which activation energy appears with a negative sign and temperature in the denominator, so lowering the barrier or raising the temperature both increase k, and the dependence is exponential rather than linear. This is why a catalyst and a temperature rise produce such large changes in rate. Concentration does not appear in the equation at all.
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About Rate Constant
The rate constant, k, connects reaction rate with reactant concentrations in a rate law and has a value fixed for a particular reaction at a given temperature. Questions involve determining k from rate data, identifying its units for different reaction orders, and applying the Arrhenius equation to temperature changes.
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