Chemistry: A titration of ethylamine with HCl.

[sondawg]

Homework Statement

For the titration of 50 mL of 0.150 M ethylamine (C2H5NH2), with 0.100 M HCl, find the pH :
a) when 10 mL more of HCl has been added than is required
b) when 75% of the required acid has been added

Homework Equations

Maybe Henderson Hasselbalch?: pH = pKa + log (base/acid)
Ka = 2.34*10^-4

The Attempt at a Solution

I honestly do not know where to go with this.

 

[sondawg]

I managed to solve most of the problem by now, just can't get the two parts still in the question.

 

[Borek]

b is Henderson-Hasselbalch equation, a is just a limiting reagent question.

See titrations.info/acid-base-titration-curve-calculation (summary will be enough).