First off, I'm confused with the concept of "rate constant." Can you explain what this means?
For a reaction A+B
C , we have the following rate equation:
Rate = k[A]
m[B]
nWhere
k is the rate constant
m and n is the order of reaction with respect to A and B respectively
I'm a beginner at this, right now I'm just trying to learn what concepts are involved with this problem.
First-order reaction have a constant half-life, so you can calculate the concentration of reactants after a given time by calculate how many half-lifes has passed at that time interval(or using mathematical formulas derived from this concept). For example, for a first order reaction with a half-life of one hour, if 3 hours have passed, the concentration of the reactant will be halved 3 times, and only 12.5% reactant remains.
There is a simple mathematical relation relating the half-life and rate constant for first-order reaction. Start by using this relation to calculate the half-life first(Refer to your textbook or search in Google if you have no idea about this relation).