Final answer:
The half-life rate constant (k) for a first-order process with a half-life of 493 seconds is calculated using the equation k = 0.693 / t1/2, resulting in a rate constant of 0.001406 s-1.
Step-by-step explanation:
To find the half-life rate constant (k) for a first order process given the half-life (t1/2) of 493 seconds, we can use the following equation derived from the first-order kinetics equation:
k = 0.693 / t1/2
Substituting the given half-life into the equation gives us:
k = 0.693 / 493 s = 0.001406 s-1.
This is the rate constant for the reaction with a half-life of 493 seconds. It represents how quickly the concentration of a reactant decreases to half its initial concentration in a first-order reaction process.