3. You have a solution at pH 12 containing 0.1 moles of histidine. Write the main chemical reaction that would take place as you are adding the final drop of: (Just indicate the functional group involved) a). 0.05 moles HCI What is the approximate pH of the solution? b). 0.05 moles NaOH 4. a). Draw the peptide Y-E-S at physiological pH (7.4). b). Calculate the pl of the peptide: c). Would this peptide be able to buffer at pH 6.5? d). How many equivalents of strong base would you have to add to the solution at pH 6.5 to reach the next buffering region? Do not base your answer on a calculation ej. What is the minimum equivalents of strong base you would have to add to the solution at pH 6.5 to make the best possible buffer? What would be the pH of your solution? No calculations are necessary to answer this