Question

1. Ibuprofen (C13H18O2) is the active ingredient in many nonprescription pain relievers. Each tablet contains 200 mg of ibuprofen, and a typical adult dose is two tablets every six hours.
• Determine the molar mass of ibuprofen. Show all steps to find the answer.
• Calculate the number of moles of ibuprofen in a single tablet. Show all steps to find the answer.
• Calculate the number of moles of ibuprofen that an adult would have taken if she took four doses of ibuprofen in one day. Show all steps to find the answer.

Help ASAP need to get this done fast

Answer 1

 Ok so since you are looking for the molar mass, you must multiply each element in the formula for ibuprofen (C13H18O2) by each elements respective masses so C-12 H - 1 and O-16. 
C (12*13)= 156 
H (1*18) = 18 
O (16*2) = 36 
now add all together to get the molar mass (156 + 18 + 36) = 206 grams of C13H18O2 (one mole) 

To calculate the number of moles in an ibuprofen tablet you need to change 200 mg to grams 
200 mg = .2 g 
now one mole of ibuprofen is 206 grams so .2g of ibuprofen would be .2/206 = .00097087 moles of ibuprofen in a single tablet. 

To calculate the moles of ibuprofen that an adult would have consumed with four doses is simply taking the moles from the previous answer and multiplying it by 4 to get the total moles of four doses so .00097087*4 = .0038835 moles of ibuprofen in four doses

Answer 2

Answer :

The molar mass of ibuprofen is, 206.29 g/mole.

The number of moles of ibuprofen in a single tablet is, 0.000969 moles

The number of moles of ibuprofen in four doses is, 0.007752 moles

Solution : Given,

Molar mass of carbon = 12.01 g/mole

Molar mass of hydrogen = 1.01 g/mole

Molar mass of oxygen = 15.99 g/mole

1) Now we have to calculate the molar mass of ibuprofen.

Molar mass of ibuprofen, $C_{13}H_{18}O_2$ = $(13\times 12.01)+(18\times 1.01)+(2\times 15.99)=206.29g/mole$

The molar mass of ibuprofen = 206.29 g/mole

2) Now we have to calculate the moles of ibuprofen.

Formula used : $Moles=\frac{Mass}{\text{ Molar mass}}$

Given : Mass of ibuprofen = 200 mg = 0.2 g         (1 mg = 1000 g)

$\text{ Moles of ibuprofen}=\frac{\text{ Mass of ibuprofen}}{\text{ Molar mass of ibuprofen}}=\frac{0.2g}{206.29g/mole}=0.000969moles$

The moles of ibuprofen = 0.000969 moles

3) Now we have to calculate the number of moles of ibuprofen for four doses.

Number of tablets in one dose = 2

Total number of tablets in 4 doses = 4 × 2 = 8

Number of moles of ibuprofen in 8 tablets =

$\text{ Number of moles of ibuprofen in 1 tablet}\times \text{ Total number of tablets}=0.000969\times 8=0.007752moles$