Weeks 9 & 10 Achieve HW Question 11

[Ashley Peterson 2C]

Hello! This question was one that I believe was a lot similar to one of the syllabus outline problems..
for whatever reason I managed to calculate part 1 and part 3 but not part 2. Would anyone be able to guide me through where I'm doing wrong?? Help is much appreciated!
[The blank part is the one I'd like to figure out to make this clear]

[Avantika MOhan_2B]

For this question, make sure you are converting hours to seconds when you are calculating. Since we know it is first order, we will use the equation wherein: [At] = -kt + [A0]. The question has given us A0 and we know k from the question. We will convert hours to seconds by multiplying by 3600 (60*60) and then put it all together to get the concentration after 2.3 hours. hope this helped!

[Ariana 1D]

for part b, I converted t in hours to t in seconds because my k was in seconds and then I used the equation [A]_t = [A]_0 * e^ (-kt) and plugged in [A]_0, k, and t which they all provide you in the problem. hope that helps