A Weak Organic Acid Pka 4 82 Is Being Studied As A Potential Broadleaf Herbicide

A weak organic acid (pKa = 4.82) is being studied as a potential broadleaf herbicide. One aspect of the study includes testing for its presence in water samples taken from a run-off of a field. The acid has a distribution ratio of 62 between water and chloroform at a pH of 3.42.

a. Using 30.0 mL of chloroform, what fraction of the compound will be extractedfrom a 50.0 mL field sample at pH = 3.42?

b. What fraction of the acid in the 50.0 mL sample would be extracted, again at pH3.42, using three 10.0 mL portions of chloroform?

c. If the pH of the solution was changed to 6.00, what fraction would be extractedusing 30.0 mL of chloroform with a 50.0 mL field sample?

d. Qualitatively, predict what effect a lower pH would have on the extraction

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