Question

The rate of a reaction, 2A + B $\rightarrow$ Products, is $Rate = k[A]^2[B]$. The value of the rate constant (k) can be increased by:

• A. increasing the concentration of A alone.
• B. increasing the concentration of B alone.
• C. increasing the concentrations of A and B simultaneously.
• D. increasing the temperature.

Hint:

Constants stay constant unless you change the Temperature!

Answer 1

The Correct Option is D

Step 1: Concept
The rate constant ($k$) is independent of the concentrations of the reactants.

Step 2: Meaning
Concentration changes affect the "Rate" but not the "Rate Constant" $k$.

Step 3: Analysis
According to the Arrhenius equation ($k = Ae^{-Ea/RT}$), the rate constant is a function of temperature ($T$) and activation energy ($E_a$).

Step 4: Conclusion
Increasing the temperature provides more kinetic energy to molecules, increasing the value of $k$. Final Answer: (D)