(a) A long thin molecule has a greater friction coefficient than a short fat molecule. Predict whether fumarate or maleate will have greater electrophoretic mobility.

(b) Electrophoresis is run with the injection end positive and the detection end negative. At pH 8.5, both anions have a charge of -2. The electroosmotic flow from the positive terminal to the negative terminal is greater than the electrophoretic flow, so these two anions have a net migration from the positive to the negative end of the capillary in electrophoresis. From your answer to part (a), predict the order of elution of these two species.
(c) At pH 4.0, both anions have a charge close to -1, and the electroosmotic flow is weak. Therefore, electrophoresis is run with the injection end negative and the detection end positive. The anions migrate from the negative end of the capillary to the positive end. Predict the order of elution.

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COT O,C 02C CO2 Fumarate