Question

In Arrhenius equation, $k=A{e}^{\left(\frac{E_a}{RT}\right)}.$ A may be termed as the rate constant at:

• A. Very low temperature
• B. Very high temperature
• C. Zero activation energy
• D. The boiling temperature of the reaction mixture

Answer 1

Answer: (B), (C)

Very high temperature
Zero activation energy

As we know, the higher the temperature, the faster a given chemical reaction will proceed. Quantitatively, this relationship between the rate a reaction proceeds and its temperature is determined by the Arrhenius Equation.

At higher temperatures, the probability that two molecules will collide is higher. This higher collision rate results in higher kinetic energy, which affects the activation energy of the reaction. The activation energy is the amount of energy required to ensure that a reaction happens.

This calculator calculates the effect of temperature on reaction rates using the Arrhenius equation.

$k=A{e}^{-E_a/RT}$, where k is the rate coefficient, A is a constant, Ea is the activation energy, R is the universal gas constant, and T is the temperature (in kelvin).

Here, activation energy and pre-exponential factor are always temperature independent.

$k=A$, when $T\to \infty or{E}_a=0$ or both.

Hence, the correct options are $\text{B}$ and $\text{C}$