The half-life of the first order reaction, A → products, is 33.8 s. What was the original concentration, [A]O in mol/L, if after 2.5 minutes, the concentration of A is 0.0796 mol/L? Round your answer to three significant figures.
I think the formular is 1/(A)t = kt + 1/(A)0
So I tried 1/33.8s = (0.0796)
so it = 1/0.0796.
I know this is not correct, but I think I'm using the right formula. I looked back at my notes and nothing is really making any sense, but this formula.