The ratio of rate constants using the Arrhenius equation determines how many times faster ozone decomposes at the top than the bottom of the ozone layer due to temperature variations.
The rate of a chemical reaction is influenced by temperature through the Arrhenius equation, which states that the rate constant (k)) of a reaction is exponentially dependent on temperature:
![\[ k = A \cdot e^{-(E_a)/(RT)} \]](https://img.qammunity.org/2024/formulas/physics/high-school/vqluhwr8tu34uzlso2ikj0mzzc9pl2kh2w.png)
where:
- A is the pre-exponential factor (frequency factor),
-
is the activation energy,
- R is the ideal gas constant, and
- T is the temperature in Kelvin.
Considering the given temperature range, we can analyze the ratio of the rate constants at the top
and bottom
of the ozone layer:
![\[ (k_1)/(k_2) = \frac{A \cdot e^{-(E_a)/(R \cdot T_1)}}{A \cdot e^{-(E_a)/(R \cdot T_2)}} \]](https://img.qammunity.org/2024/formulas/physics/high-school/fq32v4ua7f2m3lbtz882spv2cntuwpdgzw.png)
Simplifying, we find:
![\[ (k_1)/(k_2) = e^{(E_a)/(R) \left((1)/(T_2) - (1)/(T_1)\right)} \]](https://img.qammunity.org/2024/formulas/physics/high-school/ogy8euq2j6iv2wxll3fc1or9k2oz2adcw2.png)
Given that
and R are constants, we can evaluate the exponential term to find the ratio of rate constants.
This ratio represents how many times faster ozone decomposes at the top compared to the bottom of the ozone layer. As temperature increases, the rate of reaction generally increases, and since
, the exponential term will be positive, indicating a higher rate at the top.