The theoretical limit for extracting solute Sfrom Phase1(volumeV1)into phase2 (volumeV2)is attained by dividing V2into an infinite number of infinitesimally small portions and conducting an infinite number of extractions. With a partition coefficient, K=[S]2/[S]1the limiting fraction of solute remaining in phase 1is2qlimit=e-(V2/V1)K(V1=V2=50mLandK=2). Let volume V2be divided intoequal portions to conduct extractions. Find the fraction of S extracted into phase 2 for n = 1,2, and 10extractions. How many portions are required to attain 95%of the theoretical limit?

Short Answer

Expert verified

To conclude the number of portions required in order to attain the 95% of the limit would be and the extracted fraction would be

0.95×0.864655=0.82143

Step by step solution

01

Given Information:

For Partition coefficient K=S2/S1,the limited fraction of solute in is

1is2qlimit=e-(V2/V1)K(V1=V2=50mLandK=2).The fraction of is extracted for forn=1,2,and10extractions.

02

To Find the fractions of the solute :

Limited fractions of solute remaining in first phase

qlimit=eV2/V1kqlimit=e-50mL/50mL×2qlimit=0.135335

The maximum fraction extracted would be

1-qlimit=1-0.1353351-qlimit=0.864665

S.NO

A

B

C

D

E

F

1

n

V2/n

Q

1-q

% Extracted

2

1

50.0

0.333

0.667

77.1

3

2

25.0

0.250

0.750

86.7

4

3

16.7

0.216

0.784

90.7

5

4

12.5

0.198

0.802

92.8

6

5

10.0

0.186

0.814

94.1

7

6

8.3

0.178

0.822

95.1

8

7

7.1

0.172

0.828

95.7

9

8

6.3

0.168

0.832

96.2

10

9

5.6

0.164

0.836

96.6

11

10

5.0

0.162

0.838

97.0

For column C calculations as q=V1V1+D×V2n

For column D calculations as 1-q

For column E calculations as 1-q1-qlimit

To conclude the number of portions required in order to attain the of the limit would be and the extracted fraction would be

0.95×0.864655=0.82143

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