Question

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

Answer 1

Molar mass of caffeine,C₈H₁₀N₄O₂ is = 8(12)+10(1)+4(14)+2(16) = 194 g/mol

Molar mass of Caffeine Salicylate , C₁₅H₁₆N₄O₅ is = 15(12)+16(1)+4(14)+5(16)= 332 g/mol

Caffeine reacts with excess of Salicylic Acid produces Caffeine Salicylate

C₈H₁₀N₄O₂ + C₇H₆O₃ C₁₅H₁₆N₄O₅

According to the balanced equation ,

1 mole of Caffeine reacts with excess of Salicylic Acid produces 1 mole of Caffeine Salicylate

So 194 g of Caffeine reacts with excess of Salicylic Acid produces 332 g of Caffeine Salicylate

                                                               OR

194 mg of Caffeine reacts with excess of Salicylic Acid produces 332 mg of Caffeine Salicylate

50 mg of Caffeine reacts with excess of Salicylic Acid produces M mg of Caffeine Salicylate

M = (332 / 194 ) x 50

    = 85.6 mg of Caffeine Salicylate

Therefore the Theoretical Yield of Caffeine Salicylate is 85.6 mg