9 of 20 Sapling Learning If a buffer sokution is 0220 M in a

9 of 20 Sapling Learning If a buffer sokution is 0.220 M in a weak base (K, -8.3 x109 and 0.420 M in its conjugate acid, what is the pH? pH= Next Exit

Solution

Kb = 8.3 x 10^-5

pKb = -log Kb = -log (8.3 x 10^-5)

pKb = 4.08

concentration of weak base = 0.220 M

conjugate acid = 0.420 M

pOH = pKb + log [salt / base]

      = 4.08 + log [0.420 / 0.220]

pOH = 4.36

pH = 9.64