Chemistry Problems about Aspirin

Q:-What is the theoretical yield of aspirin in an experiment if you start with 2.0 g of salicylic acid and 5.0 mL of acetic anhydride (density = 1.08 g/mL)

A:-C7H6O3 + C4H6O3 <---> C9H8O4 + C2H4O2

So for 1 mole of salicylic acid and 1 mole of acetic anhydride, you get 1 mole of acetylsalicylic acid and 1 mole of acetic acid.

To find the mass of 5 mL of acetic anhydride:

M = DV

1.08 g/mol x 5 mL = 5.4 g

Now you need to find the number of moles of s.a you have (which will equal the number of moles of acetylsalicylic acid):

mol = g/molecular mass

2.0 g / (138.118 g/mol) = 0.014 mol

Now all you have to do is calculate how may grams 0.014 mol of acetylsalicylic acid is:

g = MM x mol

244.154 g/mol x 0.014 mol = 3.42 g