Calculate the pH of 100.0 mL ofa buffer that is 0.070 M NH4CL and 0.130 M NH3 before and after the addition of 1.00 ml of 5.55 M HNO3.

Question

Before = ?
After = ?

I know the base is NH3 and the acid is NH4Cl!

Answer 1

millimols NH3 = M x mL = ?
mmols NH4Cl = mL x M = ?
mmols HNO3 = mL x M = ?

Before:
Use the Henderson-Hasselalch equation.

After:
Construct an ICE chart frp, below and add the HNO3. Recalculate using the HH equation.
............NH3 + H^+ ==> HNH4^+
initial.....
add HNO3 ........
change
equil.