Question

What is the effect of rate constant on temperature?

Answer 1

Hint: In order to determine the effect of temperature on rate constants, determine all the factors that influence the mechanism through which a reaction takes place. The increase in temperature is directly proportional to the thermal energy of the reacting molecule.

Complete answer:
Chemical kinetics deals with the rate at which various reactions take place. Determining reaction rates helps us visualize how fasts the reactants are being consumed or the products are being formed.
The reaction rates are influenced by various factors like the concentration of the reacting species at a particular time, the order of the reaction, the presence or absence of a catalyst, the activation enthalpy and the temperature at which the reaction takes place.
The rate constants are numerical values of rates in chemical kinetics measured at unit concentration of the reactants. The rate constant values do not change with the changing concentrations of a reactant and can only be altered by varying the temperatures at which the reaction takes place.
Most theories in chemical kinetics assume that the reactions take place by the help of the reacting molecules colliding with each other. The speed of these collisions tend to determine the rates of the reactions.
An increase in temperature enhances the net thermal energy of the reacting molecules resulting in higher rate constants.
The Arrhenius theory gives the relationship between the temperature and rate constant which can be written as follows:
\[k = A{e^{\dfrac{{ - {E_a}}}{{RT}}}}\]
Upon increasing temperature the negative power of the exponential decreases and the overall value of \[k\] increases.
Hence, the rate constant increases with increasing temperature.

Note:
The Arrhenius theory also gives a relationship between the rate constant and the activation enthalpy \[{E_a}\] . While establishing a relationship between temperature and rate constants, it is assumed that the activation enthalpy is independent of the temperature.