Chemical analysis reveals capsaicin to contain 71.0% of carbon, 8.60% hydrogen, 15.8% oxygen and 4.60% nitrogen.

a) Determine the empirical formula of capsaicin
b) Each molecule contains one atom of nitrogen. What is the molecular formula of capsaicin?

I figured out the empirical formula but I got stuck on the molecular formula.

5 answers

It will be easier to catch the error if you post what you have done.
Well i found the moles of each element.
Carbon has 5.91mol
Hydrogen has 8.51mol
Oxygen has 0.988mol
Nitrogen has 0.328mol
Then I put the moles as subscripts and divded each subscript by the lowest amount of moles (nitrogen with 0.328mol). Then as the empirical formula I get C18H26O3N.

So in order to get the molecular formula, I need the actual mass of the molecular formula but I do not know how to find it. Because you have to divide the mass of the molecular formula by the mass of the empirical formula.
Your formula of C18H26O3N is correct. The last part is done with the Each molecule contains one atom of nitrogen. What is the molecular formula of capsaicin?
The catch is in the statement. If each molecule contains one atoms of N, then the empirical formula must be the same as the molecular formula for your empirical formula contains just 1 atom of N.
Awesome! Thanks
marty you a real one i kno im from the future but let me tell u what i had a quiz on that exact question like bruh they still using questions from 2007 i was literally 2 years old at that time but d am who knew i was gonna answer this in 2022 u a real one fr fr