Question

a) Would 2-propanol be a suitable solvent to extract caffeine from an aqueous tea solution? Explain?

b) You want to use 45 ml total of your extraction solution. Is it better to use three extractions of 15 ml each or one extraction of 45 ml? Explain your answer?


Thanks!

Answer 1

Do you have the K for the extraction using propanol. If so that should tell you. For part b it is ALWAYS better (f better is better yield) to extract with 3 portions of a solvent over 1 extraction with a single amount (even though 15*3 = 45).
You can run through and calculate the amount of caffeine left behind in each of 3 vs the 1 and see what difference it makes.