Question

One type of penicillin has the formula C14H20N2SO4. How many molecules of penicillin are in a pill containing 300 mg?

Answer 1

Well, you have to determine the molecular weight which is 312.385 g/mol. \[M=312,385 g/mol\]\[n=300mg * (1/312.385) mol/g = .3g * (1/312.385) mol/g = 9.6*10^{-4} mol\]1 mol consists of 6.022*10^23 particles:\[9.6*10^{-4} mol *6.022*10^{23}mol^{-1}=5.783*10^{20}\]

Answer 2

Thank you!