Question

What is the ph of a soulution made by adding 0.20 mole NH3(aq) to 0.30 mole NH4Cl and 0.10 mole KOH to 100ml of water?
Kb for NH3 (aq)=1.8x10^-5M

Answer 1

I would do this.
.......NH4^+ + OH^- ==> NH3 + H2O
I......0.3......0.......0.2.......
add............0.1................
C,....0.3-0.1..-0.1.....+0.1
E......0.2......0........0.3

Convert the mols in the E line to M (mols/L) and substitute into the Henderson-Hasselbalch equation.