posted by krystal .
a. What is the molecular weight of aspirin (C9H8O4)?
b. What is the mass of 0.00785 mol of aspirin?
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
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)