In: Chemistry
500.0 mL of 0.110 M NaOH is added to 615 mL of 0.200 M weak acid (Ka = 7.63
millimoles of acid = 0.2 x 615 =123
millimoles of base = 500 x 0.11=55
HA + NaOH ---------------------------> NaA + H2O
123 55 0 0 -----------------------------before reaction
68 0 55 55 ------------------------after reaction
in this mixture salt NaA and acid HA remains . it can form buffer
pKa = -log Ka = -log(7.63