Titration Curves

Point 1 - NaOH has not been added yet. It predominately contains H3O+ ions disassociated from HCl).

Point 2 - As NaOH is being added, H3O+ ions are being consumed by OH- ions. At this point, a reading has been taken just before neutralisation has been reached. 

Point 3 - Equivalence Point has been reached. It is halfway up the steep line. HCl and NaOH have been completely neutralised to form salt and water.

Point 4 - Addition of NaOH continues. As the concentration of OH- ions becomes in excess. 

Point 1 - NaOH has not been added yet. It predominately contains H3O+ ions disassociated from CH3COOH). [Note the change in starting pH]

Point 2 - A reading has been taken just before neutralisation has been reached. 

Point 3 - Equivalence Point has been reached. It is halfway up the steep line. CH3COOH and NaOH have been completely neutralised to form salt and water.  [Note the pH is not 7 here - do you remember why??]

Point 4 - Addition of NaOH continues. As the concentration of OH- ions becomes in excess - beyond the equivalence point the titration curves are identical to a strong acid-strong base curve. 

Point 1 - NH3 has not been added yet. It predominately contains H3O+ ions disassociated from HCl). 

Point 2 - A reading has been taken just before neutralisation has been reached. 

Point 3 - Equivalence Point has been reached. It is halfway up the steep line. NH3 and HCl have been completely neutralised to form salt and water.  [Note the pH is not 7 here - do you remember why??]

Point 4 - Addition of NH3 continues.  Note that after the equivalence point the curves are different due to NH3 being a weak base.