Chapter 17, Problem 25E

A handbook lets various procedures for preparing buffer solutions. To otter a pH =9.00, the handbook says to mix 36.00 mL of 0.200 U ${\text{NH}}_2$ with 64.00mL of 0.200 M ${\text{NH}}_{\text{4}}\text{Cl}$ .

a. Show by calculation that the pH of the solution is 9.00

b. Would you expect the pH of the solution to remain at pH = 9.00 if the 100.00 mL of buffer solution were diluted 1.0100 L? To 1000L? Explain.

c. What will be the pH of the original 100.00 mL of buffer solution if 0.20mL of 1.00M HCl is added to it?

d. What is the maximum volume of 1.00 M HCI that can be added 100.00 mL of the original buffer solution so that the pH does not drop below 8.90?