What is the Theoretical Yield of Caffeine Salicylate if we start with 50 mg of Caffeine and an excess of Salicylic Acid.

Answer 1

Caffeine + salicylic acid ==> caffeine salicylate + H2O

molar mass caffeine = 194.19 g / mole

molar mass caffeine salicylate = 332.31 g / mol

50 mg caffeine x 1 g / 1000 mg x 1 mol caffeine / 194.19 g = 2.575x10^-4 mols caffeine

mols caffeine salicylate formed = 2.575x10^-4 mols caffeine x 1 mol caffeine salicylate/mol caffeine =

2.575x10^-4 mols caffeine salicylate

Theoretical yield in grams = 2.575x10^-4 mols caffeine salicylate x 332.31 g / mol = 0.086 g = 0.09 g (1 s.f.)