Question

a. What is the molecular weight of aspirin (C9H8O4)?

180.1574 amu

b. What is the mass of 0.00785 mol of aspirin?

1.41 g

c. How many moles of aspirin are present in 100 mg of aspirin? Enter your answer in scientific notation.

5E-4 mol aspirin


d. How many molecules of aspirin are present in 5.00 g of aspirin? Enter your answer in scientific notation.

1.67E22 molecules aspirin

Answer 1

All of these are ok except for c. You don't have enough significant figures in c. You have 3 s.f. in 0.100 g; your answer should have 3 s.f. (I would buy 5.55E-4)