20 ml of 0.1 M Acetic acid and 25 ml of 0.1 M Sodium Acetate are mixed together. then 5ml of 0.1 M of NaOH is added. Find the Ph before the addition of NaOH and after the addition of NaOH??

Question

20 ml of 0.1 M Acetic acid and 25 ml of 0.1 M Sodium Acetate are mixed together. then 5ml of  0.1 M of NaOH is added. Find the Ph before the addition of NaOH and after the addition of NaOH??

DrBob222 · Answer

Use the Henderson-Hasselbalch equation to find the initial pH.
Then complete the ICE chart I've started below for the second part and substitute the final mmoles into the HH equation. (which may help you on the first part, too).
begin = 20 mL x 0.1M = 20 mmoles CH3COOH.
begin = 25 mL x 0.1M = 25 mmoles CH3COONa
add 5mL x 0.1M NaOH = 5 mmoles OH-
.......CH3COOH + OH^- ==> CH3COO- + H2O
begin....20......0.........25.......0
add .............5...................
react....-5.....-5........+5........+5
final....

james bond · Answer

Iam not quite clear about how to find the Ph before the additon NaoH... could you please show me how to solve...