Question

Every weak acid has the following unique characteristic(s):

a. at the 50% titration point the pH = pKa

b. the best buffering occurs +/- one pH unit of the pKa

c. the change in pH with added acid or base is the least when pH = pKa

d. the shape of the titration curve is essentially the same for all weak acids

e. all of the above

If the pH of a buffer with a pKa of 6 changes from pH 6 to 7 how does the [A-]/[HA] ratio change:

a. from 1/10 to 1/1

b. from 10/1 to 1/1

c. from 1/1 to 1/10

d. from 1/1 to 10/1

e. from 1/10 to 10/15

If the hydrogen ion concentration of a solution is 10^-5 M, what is the hydroxyl ion concentration:

a. 10^-5

b. 10^-1

c. 10^-2

d. 10^-9

e. 10^-5

What is the pH of a buffer with a pKa of 5 when the ratio of [A-]/[HA] is 10/1:

a. 3

b. 4

c. 5

d. 6

e. 7

If the pH is 8 what is the pOH:

a. 8

b. 4

c. 6

d. 12

e. 1

Answer 1