(This homework question has been removed due to a copyright claim submitted by K12, Inc.)

_----------_
[" okay this is what i got and im not sure if i did it right nor do i know if i answered everything the questions wanted so could you help me out please"]
_----------_

ANSWER:
C 12*13=156
H 1*18=18
O 16*2=32
156+18+32=206g/mol
200mg=0.2g
0.2g/ 206 g/mol = 9.7 x 10^-4 moles
0.00097 mol = moles of ibuprofen in 1 tablet
6 x 0.00097 moles = 0.00582 moles, or 5.82 x 10^-3 = moles of ibuprofen a day

3 answers

I didn't use calculator,but it looks correct, except the total doses..

The problem said 4 doses per day (8 pills), or 8*.00097
I agree with Bob Pursley; however, you rounded too soon for moles in one tablet. You have three s.f. in 200 mg, three in 206 g/mol and the calculator shows me 9.7087E-4 for moles in one tablet and that rounds to 9.71E-4 to three s.f. Why not just leave that number of 0.200/206 in your calculator and multiply that by 8 to arrive at the final answer, and make rounding the last thing you do? That way you don't throw away good numbers.
well thank you both that really helped...=D