Question

The specific rate constant of a first-order reaction depends upon:
(A). The concentration of the reactants
(B). The concentration of the products
(C). Time
(D). Temperature

Answer 1

Hint: The rate equation for a first-order reaction is given by
$\dfrac{d[A]}{dt}$ = k[A]
where, k is the specific rate constant
 [A] is the concentration of the reactant
Now try to remember what the expression of k was from the collision theory.

Complete step by step solution:
In the rate equation for a first-order reaction given by
$\dfrac{d[A]}{dt}$ = k[A]
The rate constants depend strongly on temperature, typically increasing rapidly with increasing T.
The specific rate constant is given by the Arrhenius equation:
$k=Ae^{\dfrac{-E_a}{RT}}$
where A and $E_a$ are constants and are characteristics of the reaction and R is the universal gas constant, and T is the absolute temperature. $E_a$ is the Arrhenius activation energy and A is the pre-exponential factor (or also known as the Arrhenius A factor). The units of A are the same as those of k. The units of $E_a$are the same as those of RT, namely, energy per mole. $E_a$ is usually expressed in kJ/mol or kcal/mol.
So, the correct answer to the problem is option B): The specific rate constant of a first-order reaction depends upon Temperature

Additional information:
The collision theory you studied in kinetics is not the most right one, historically we tested it for the decomposition of HI and the experimental values accidentally coincided with ones predicted by collision theory, this slowed down further developments in science. Until some other reactions started showing orders of magnitudes of difference and it was slowly overtaken by transition state theory.

Note: Even though in the rate equation $\dfrac{d[A]}{dt}$ = k[A] the terms for time and concentration comes, but this would be a wrong correlation with no logical basis the specific rate constant is given by $k=Ae^{\dfrac{-E_a}{RT}}$