Question

Lycopene and beta carotene are important antioxidants found in some fruits and vegetables. Suppose an organic solvent was going to be used to extract and measure lycopene from a new hybrid tomato. A sample of aqueous tomato paste was introduced into a separatory funnel. Then an organic solvent was added. The funnel contents were swirled for several minutes. After extraction, the concentration of lycopene in the organic solvent was found to be 6.5 x 10^-4M while the aqueous phase maintained a concentration of 1.5 x 10^-5. What is the value of the partition ratio (K_D) with this extraction?

Using the value of K_D from "A", what fraction of lycopene would be extracted from the aqueous tomato paste into the organic phase if you began with 100.0 mL of tomato paste and added 50.0 mL of the organic solvent?

Answer 1

Lycopene and beta carotene are important antioxidants found in some fruits and vegetables. Suppose an organic solvent was going to be used to extract and measure lycopene from a new hybrid tomato. A sample of aqueous tomato paste was introduced into a separatory funnel. Then an organic solvent was added. The funnel contents were swirled for several minutes. After extraction, the concentration of lycopene in the organic solvent was found to be 6.5 x 10^-4M while the aqueous phase maintained a concentration of 1.5 x 10^-5. What is the value of the partition ratio (K_D) with this extraction?

The partition ratio (K_D), as the ratio of the solute’s total concentration in each phase measn organic phase and aqueous phase

K_D =[Sorg]total / [Saq]total

Here [Sorg]total = 6.5 x 10^-4M

[Saq]total = 1.5 x 10^-5M

Therefore ;

K_D =[Sorg]total / [Saq]total

= 6.5 x 10^-4M/1.5 x 10^-5M

= 43.3

Or [Sorg]total =43 [Saq]total

Using the value of K_D from "A", what fraction of lycopene would be extracted from the aqueous tomato paste into the organic phase if you began with 100.0 mL of tomato paste and added 50.0 mL of the organic solvent?

K_D =[Sorg]total / [Saq]total

To demine the fraction of lycopene would be extracted from the aqueous tomato paste into the organic phase if you began with 100.0 mL of tomato paste and added 50.0 mL of the organic solvent, we use following espression:

43 [Saq]total /100] / [Saq]total/50

=21.5