<p>Three Titrations</p><p>1) HCl + NaOH (SA + SB) 3 sections a) gradual upswing in pH due to HCl reacting, and H3O+ getting diluted by added water Note: all added NaOH is getting reacted during this region, so OH- build up due to added NaOH is not the reason for pH increase. PRESENT: HCl b) equivalence pt = mole acid = mole base (both reactants are all used up!) Note: pH = 7 because Na+ and Cl- and HOH are all there is. c) final upswing – due to added excess NaOH</p><p>2) AA + NaOH (WA + SB) (Note: AA=acetic acid; A=acetate ion) 4 sections a) Initial spike due to huge influx of conj base compared to what is already there b) gradual upswing in pH due to AA reacting, and H3O+ getting diluted by added water + BUILD UP OF CONJ BASE!!!!! Note: all added NaOH is getting reacted during this region, so OH- build up due to added NaOH is not the reason for pH increase. PRESENT: AA, and A ION – which is a buffer (all NaOH has reacted) c) equivalence pt = mole acid = mole base (both reactants are all used up!) Note: pH > 7 because at eq point all acid is gone and conj base is present d) final upswing – due to added excess NaOH. Conj Base also present but not nearly as important</p><p>3) NH3 + HCl (WB + SA) 4 sections a) Initial drop due to huge influx of conj acid compared to what is already there b) gradual downswing in pH due to NH3 reacting, and OH- getting diluted by added water + BUILD UP OF CONJ ACID!!!!! Note: all added HCl is getting reacted during this region, so H3O+ build up due to added HCl is not the reason for pH decrease. PRESENT: NH3 and NH4+ ion – which is a buffer (all HCl has reacted) c) equivalence pt = mole acid = mole base (both reactants are all used up!) Note: pH < 7 because at eq point all base is gone and conj acid is present d) final downswing – due to added excess HCl. Conj acid also present but not nearly as important</p>