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1. Fraction of caffeine in aqeuous later = Vaq / Kd .VCH2Cl2 + Vaq Volumes -->  V...

1. Fraction of caffeine in aqeuous later = Vaq / Kd .VCH2Cl2 + Vaq

Volumes -->  V CH2 Cl2 (dichloromethane) and Vaq (water) in each layer. Assume the KD for caffeine between dichloromethane and water is 5.

Assume in experiment : 90.0 mg of caffeine dissolved in 100mL of water and you shook it with 12 mL of dichloromethane, what would be the mass of caffeine that was left in the aqueous layer?

My answer was 56.25 mg ( not sure if it is right)

2.  Find mass of caffeine left in the initial aqueous layer from Q1 after extracting it three times, using 12 mL of dichloromethane each time? (Btw fraction remaining in the aqueous layer is the same each time; if there was 1/2 left the first time, there would be 1/2 x 1/2 of the original amount left the second time, and 1/2 x 1/2 x 1/2 left the third time)

My answer is 14.0625mg of caffeine , again not sure its right

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Answer #1

Ans-2 this answer is given is not correct..

And the answer is left the third time is 13.73 mg.

Please give me rating and like this answer....

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