la) Biliverdin is a pigment produced by tree frogs that causes them to look green - its structure in its fully ionized form is shown below. It contains two ionizable groups, both of which are carboxyl groups; one has a pK, of 3.9 and the other has a pK₂ of 5.3. What would the net charge on the whole molecule be if you dissolved it in an aqueous solution at pH 7.0? Briefly explain how you determined the charge. H₂C H₂C H3C Coo coo CH3 H3C H₂C 1b) What pH would you need to adjust the solution of biliverdin to in order to get this molecule to have a net charge of 0 (neutral or uncharged) essentially 100% of the time? Briefly explain why you chose that pH.

la) Biliverdin is a pigment produced by tree frogs that causes them to look green - its structure in its fully ionized form is shown below. It contains two ionizable groups, both of which are carboxyl groups; one has a pK, of 3.9 and the other has a pK₂ of 5.3. What would the net charge on the whole molecule be if you dissolved it in an aqueous solution at pH 7.0? Briefly explain how you determined the charge. H₂C H₂C H3C Coo coo CH3 H3C H₂C 1b) What pH would you need to adjust the solution of biliverdin to in order to get this molecule to have a net charge of 0 (neutral or uncharged) essentially 100% of the time? Briefly explain why you chose that pH.

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter20: Carboxylic Acids And Nitriles

Section20.4: Substituent Effects On Acidity

Problem 7P: Dicarboxylic acids have two dissociation constants, one for the initial dissociation into a...

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