What is the pH of a buffer containing 0.25 M NH3 and 0.45 M NH4Cl?

1) The pH of a buffer system containing NH3 and NH4Cl is found to be 9.35. Calculate the ratio NH3/NH4Cl. 2) The pH of a buffer system containing Na2HPO4 and KH2PO4 is found to be 6.66. Calculate the ratio Na2HPO4/KH2PO4.
6. (a) Calculate the pH of the 0.39 M NH3/ 0.73 M NH4Cl buffer system. pH = (b) What is the pH after the addition of 20.0 mL of 0.075 M NaOH to 80.0 mL of the buffer solution? pH =
Find the pH of a buffer that consists of 0.26 M NH3 and 0.18 M NH4Cl (pKb of NH3 = 4.75).
a) Calculate the pH of a buffer that is 0.20 M NH3 and 0.20 M NH4Cl Correct? b) Calculate the pH after addition of 10 mL 0.10 M HCl to 65 mL of the buffer? c) Calculate the pH after addition of 5 mL of 1.0 M LiOH to 200 mL of the buffer?
Calculate the pH of a 0.20 M NH3/0.20 M NH4Cl buffer after the addition of 25.0 mL of 0.10 M HCl to 65.0 mL of the buffer.
Calculate the pH of a 0.20M NH3 / 0.20M M NH4Cl buffer after the addition of 15.0 mL of 0.10 M HCl to 65.0 mL of the buffer. (Kb = 1.8 x 10-5)
A 1.0-L buffer solution initially contains 0.25 mol of NH3 (Kb=1.76×10−5) and 0.25 mol of NH4Cl. In order to adjust the buffer pH to 8.85, should you add NaOH or HCl to the buffer mixture? What mass of the correct reagent should you add?
What is the pH of the best buffer that can be prepared from NH3 and NH4Cl? Kb = 1.8 x 10-5 for NH3. please show your work
Calculate the pH of 0.25 M NH4CL given kb= 1.76x10^-5 for NH3 (ans. 4.92)
What is the ratio of [NH4Cl]/[NH3] in order to make a NH3/NH4Cl buffer solution with pH=8.70. (Kb for NH3 is 1.8 x 10^–5)