Chemistry Forums for Students > Undergraduate General Chemistry Forum

buffer solution

(1/2) > >>

Fish200398:
Problem 1.
A physician wishes to prepare a buffer solution at pH = 3.82 that if ciently
resists changes in pH yet contains only small concentrations of the buffering
agents. Determine which one of the following weak acids, together with its
sodium salt, would probably be best to use: m-chlorobenzoic acid, Ka = 1.04e-4
; p-chlorocinnamic acid Ka = 3.89e-5 ; 2,5-dihydroxybenzoic acid, Ka = 1.08e-3
; or acetoacetic acid, Ka = 2.62e-4. Explain.

do we use Henderson-Hasselbalch?

AWK:
HH equation is enough

Fish200398:
My theory is the concentration of acid and its conjugate in their sodium salts is the same. Therefore, protons concentration depends solely on Ka. And find pH of the acids which close to pH 3.82. Is it true?

Babcock_Hall:
Why do you do that the concentration of acid and its conjugate base are the same?

Fish200398:
If not the same then how to count the protons concentration?

The concentration of its conjugate base is depend on the concentration of the sodium

Navigation

[0] Message Index

[#] Next page