PROBLEM SOLVING 1 AND 2 ONLY logarithm of a ratio which can be solved by performing the antilogarithm of pH/pKa:10pH-pKa [base]An example of how to use the Henderson-Hasselbalch equation to solve for the pH of a buffer solution is as follows:1.What is the pH of a buffer solution consisting of 0.0350 M NH3 and 0.0500 M NH4+ (Ka for NH4+ is 5.6 x 10-10)?The equation for the reaction is:NH+ H+ + NH3Assuming that the change in concentrations is negligible, in order for the system to reach equilibrium, the Henderson-Hasselbalch equation will be:|NH:%3D['HN0.03501301+vd = HdpH = 9.25 +log ('0.0500%3DpH = 9.095Activity3. True or False!Directions: Write T if the statement is correct and F if otherwise. Write your answer before the number.1. If the buffer is made with a base and its conjugate acid, the pH can be adjusted using a weak acid like HCl.2. A buffer's pH changes greatly when a small amount of strong acid or base is added to it.3. A good buffer mixture should have about equal concentrations of both of its components.4. The strength of a weak acid (buffer) is usually represented as an equilibrium constant.5.The Henderson-Hasselbalch equation connects the measurable value of the pH of a solution with the theoreticalvalue pKa.Activity 4. It's Solving Time!Directions: Solve the following problem. Write your complete solutions.1. What is [H3O'] in a solution of 0.25 M CH3CO2H and 0.030 M NACH3CO2?CH3CO2H(aq)+H2Om=H30°(aq)+CH3CO2 (ag)2. What is [OH] in a solution of 0.125 M CH3NH, and 0.130 M CH3NH3CI?CH3NH2(aq)+H2Ou=CH3NH3 (aq)+OH (aq)K=1.8x105(be)Kp=4.4x10(be)Processing questions:1. Why is understanding of the concept of pH important?2. Why are buffer solutions relevant to life?Page | 5

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Answered: PROBLEM SOLVING 1 AND 2 ONLY

Science

Chemistry

PROBLEM SOLVING 1 AND 2 ONLY

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter15: Acid–base Equilibria

Section: Chapter Questions

Problem 107AP

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