Using the ICE method for neutralisation Mols Propanoic acid Mols NaOHMols Propanoate Initial (I) x10 -3 x.108 = Change (C) Equilibrium (E) Concentration = L c propanoic acid = molL -1 c propanoate = molL -1 pH = pKa + log [base] [acid] = log = log = = 4.36
Strong base- strong acid Strong base- weak acid Strong acid- weak base Weak base – weak acid pH at EP 7 8 8 8 8 5555 7777 Length of vertical region Long ( 8 pH units) Short ( 3 pH units) Not present pH at start 1111 3333 11 3333 Buffer zone Not present presentpresent 2 present
Volume Conc. Moles