### solving for time elapsed

Posted:

**Thu Mar 14, 2019 12:16 pm**15.35 The half-life for the second-order reaction of a substance A is 50.5 s when [A]0 0.84 molL. Calculate the time needed for the concentration of A to decrease to (a) one-sixteenth; (b) one-fourth; (c) one-fifth of its original value.

Can someone please explain how to solve part (a)?

I'm pretty sure I have to use the half-life equation to find k and then use the integrated equation to find T but my answer is not the same as the textbook.

Can someone please explain how to solve part (a)?

I'm pretty sure I have to use the half-life equation to find k and then use the integrated equation to find T but my answer is not the same as the textbook.