Ionic EquilibriumHard
Question
An ammonia - ammonium chloride buffer has a pH value of 9 with [NH3] = 0.25. What will be the newpH if 500 ml 0.1 M KOH is added to 200 ml buffer solution (Kb = 2 × 10-5) [log 2 = 0.3]
Options
A.8.4
B.9.6
C.5.6
D.4.4
Solution
5 = pKb + log
[NH4+] = 0.5
[NH3] = 0.25
m moles of KOH added = 50
NH4+ + OH- → NH3 + H2O
100 50 50
50 0 100
pOH = pKb + log
pOH = 4.7 - 0.3 ⇒ 4.4
pH = 9.6

[NH4+] = 0.5
[NH3] = 0.25
m moles of KOH added = 50
NH4+ + OH- → NH3 + H2O
100 50 50
50 0 100
pOH = pKb + log

pOH = 4.7 - 0.3 ⇒ 4.4
pH = 9.6
Create a free account to view solution
View Solution FreeMore Ionic Equilibrium Questions
In water, the acid HCIO4. HCI, H2SO4 and HNO3 exhibit the same strength as they are completely ionised in water (a base)...Which would decrease the pH of 25 ml of a 0.01 M solution of hydrochloric acid? The addition of...The pH of 0.1 M – N2H4 solution is (For N2H4, Kb1 = 3.6 × 10−6, Kb2 = 6.4 × 10−12, log 2 = 0.3, log 3 = 0.48)...Which of the following salts will give highest pH in water?...100 mL of 0.02 M benzoic acid (pKa = 4.2) is titrated using 0.02 M NaOH. pH after 50 mL and 100 mL of NaOH have been add...