{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Lecture 21 - Lecture 21 Buffers A buffer is a solution of...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Lecture 21: Buffers A buffer is a solution of an acid and its conjugate base, where the addition of a small additional amount of either will only have a negligible effect on the pH. This occurs when the initial concentrations of both the acid and conjugate base are >10%. Recall the essential equation: [H+][B]/[HB+] = Ka. In the problems that we have done so far, the initial solution consisted of ONE of the species HB+ or B added to water. Also, one of the species is assumed to be in much larger concentration at equilibrium than the other one. In this situation, further additions of either HB+ or B will change the pH substantially. Let’s say that a large amount of weak acid HB+ is present. We have been assuming that [H+] and [B] are small and equal. Obviously, adding still more HB+ will increase [H+], because Ka has to stay constant. If we add even a small further amount of B, [H+] will decrease considerably. Now, let’s consider a different case, that of buffers. In a buffer solution, significant amounts of both B and HB+ are added to form the initial solution.
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern