What is the limiting reagent?

Question

Which is the limiting reagent?
2.000g C7H6O3(salicylic acid) + 5.00mL C4H6O3(acetic anhydride) -->C9H8O4(asprin) + HC2H3O2(acetic acid)

D=1.08g/mL

How many grams of Asprin should be produced from the reaction mixture?

Answer 1

You have to do two stoichiometry calculations to answer your question.

First start witth he 2.000 g slalicylic acid. Convert to moles by dividing by the molecular mass. The molar ratio is 12:1, so that part is easy. Now convert the moles of aspirin to grams.

Now the acetic anhydride. You must first convert the 5.00 ml to grams using the density of 1.08 g/ml. Now proceed as above. Convert to moles, the molar ratio is 1:1 and then to grams of aspirin.

Ther reactant that gives the you least amount of aspirin is limiting. Your calculation also gives you the answer to part 2.

Answer 2

The salicylic acid is the limiting reagent because you only have 0.0145 moles of it and you have 0.0529 moles of acetic anhydride. It's a 1:1 ratio. You end up with 2.61 grams of aspirin.