We’re being asked to calculate the concentration of reactant remaining from 0.135 M after 125 seconds. The rate constant of the reaction is 0.0185 s–1.
We don’t know the order of the reaction but we can quickly figure it out from the rate constant.
Recall that the unit for the rate constant is given by:
where n = order of the reaction.
The given rate constant only has s–1 as its units, which means n = 1 and the reaction follows first-order kinetics.
The integrated rate law for a first-order reaction is as follows:
[A]t = concentration at time t
k = rate constant
t = time
[A]0 = initial concentration
A reaction has a rate constant of 0.0185 s -1 and the only reactant has an initial concentration of 0.135 M. What is the concentration in molarity of this reactant after 125 seconds?
A. 4.84 x 10-5
Frequently Asked Questions
What scientific concept do you need to know in order to solve this problem?
Our tutors have indicated that to solve this problem you will need to apply the Identifying Reaction Order concept. If you need more Identifying Reaction Order practice, you can also practice Identifying Reaction Order practice problems.
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