A hexane solution has equal concentrations of two antioxidants A and B. Antioxid

Question

A hexane solution has equal concentrations of two antioxidants A and B. Antioxidant A has a distribution ratio of 3 between acetonitrile and hexane while antioxidant B has a distribution ratio of 0.33. A 10 mL portion of the hexane solution was extracted successively with two 10 mL portions of acetonitile and the two acetonitrile extracts were combined. Calculate the percentage of the extracted antioxidants in the acetonitrile fractions and comment on the recovery and selectivity of each extraction.

Explanation / Answer

Lets consider antioxident A and B that is dissolved in 10ml of Hexane is 10mg each

given that AAcetone/Hex= 3 and that of BAcetone/Hex= 0.33

Now when we extract above 10 ml of hexane first time with 10 ml of acetone we wil get following amount of A and B extracted,

A =A(Acetone)/A)Heaxane) = 3/1 ; for first 10 ml extraction out of 10mg of A we would get 3 mg od A extrcated in acetone and 0.33 mg of B in 10ml extract.

During the second 10ml extrcation concnetration of A and B in hexane would be 7 and 9.27 respectively; so this time amount of A extrcated = 3*7/10= 2.1 and amout of B extrcated= 9.27*0.33/10= 0.305

now when twe pull both acetone fraction together Amount of A= 3+21= 5.1

and B= 0.33+0.305= 0.635

% of A extrcated = 5.1/10*100= 51% and % of B extracted = 0.635/10*100= 6.35%

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.