You want a solution that will buffer the addition of either 10 micromoles of acid or 10 micromoles of base. Total buffer concentration is equal to the concentration of the acid plus the concentration of salt of the acid. Which of the following buffers would you use if you wanted to buffer a solution at pH=6.9?
a) buffer A with a pKa of 7.5 and buffer concentration of 10 nanomolar
b) buffer B with a pKa of 6.6 and a buffer concentration of 10 micromolar
c) buffer C with a pKa of 7.9 and a buffer concentration of 10 micromolar
d) buffer D with a pKa of 6.6 and a buffer concentration of 100 micromolar
e) buffer A with a pKa of 7.4 and a buffer concentration of 100 micromolar
the answer is D. You can dismiss choices a, c and e, as their starting pH is either too far off, or the ...
The buffering capacity for micromoles of acids are determined.