Next Step Fl 5 B/b Exam Questions (27 Terms) With Verified Definitions Updated 2024

33. How would the alkaline ability of the zwitterion form of HEPES (pictured below), another of Good's buffers, compare to that of the zwitterion form of PIPES? A. HEPES would be more alkaline, since the removal of the sulfonyl group reduces the ability of the conjugate base to delocalize electron density via resonance, thereby increasing its reactivity. B. HEPES would be less alkaline, since the removal of the sulfonyl group reduces the ability of the conjugate base to delocalize electron density via resonance, thereby increasing its reactivity. C. HEPES would be more alkaline, since the removal of the sulfonyl group reduces the availability of acidic hydrogens in its zwitterion form. D. HEPES would be less alkaline, since the removal of the sulfonyl group reduces the availability of acidic hydrogens in its zwitterion form. {Ans: C is correct. This question has two parts: first, will HEPES be more or less alkaline (basic) than PIPES, and second, how is this effect promoted by the loss of the sulfonyl group present in PIPES. The most obvious difference is that PIPES (in the structure pictured) includes two highly acidic protons, while HEPES includes only one. In the zwitterionic form of HEPES, the nitrogen