Predicted pH for salt solutions (1 M)
 Salt   pH
KCN

strong base, weak acid salt

K+ + H2O Equilibrium double arrow NR

CN- + H2O Equilibrium double arrow HCN + OH-

>7
KC2H3O2

 strong base, weak acid salt

K+ + H2O Equilibrium double arrow NR

C2H3O2- + H2O Equilibrium double arrow HC2H3O2 + OH-

>7
 NH4Cl

weak base, strong acid salt

NH4+ + H2O Equilibrium double arrow NH3 + H3O+

Cl- + H2O Equilibrium double arrow NR

<7
  NH4 NO3

weak base, strong acid salt

NH4+ + H2O Equilibrium double arrow NH3 + H3O+

NO3- + H2O Equilibrium double arrow NR

<7
 NH4CN

NH3 stronger than HCN

NH4+ + H2O Equilibrium double arrow NH3 + H3O+

CN- + H2O Equilibrium double arrow HCN + OH-

>7
NH4C2H3O2

pKb NH3 = pKa HC2H3O2 

NH4+ + H2O Equilibrium double arrow NH3 + H3O+

C2H3O2- + H2O Equilibrium double arrow HC2H3O2 + OH-

7

 

 

 

 

Stephen E. Bialkowski's relative fractions of phosphoric acid species with pH

 

 

Stephen E. Bialkowski's Phosphoric Acid Titration Curve

 

 

 

 

H3PO4 Equilibrium double arrow H+ + H2PO4- Equilibrium double arrow 2 H+ + HPO42- Equilibrium double arrow 3 H+ + PO43-

Rxn   Ka  pKa
 H3PO4 Equilibrium double arrow H+ + H2PO4-  Ka 1 = 7.5 x 10-3  2.2
 H2PO4- Equilibrium double arrow H+ + HPO42-  Ka 2  = 6.2 x 10-8  7.2
HPO42- Equilibrium double arrow H+ + PO43-  Ka 3  = 4.8 x 10-13  12.7

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Elements Video PT Video


© R A Paselk

Last modified 10 May 2013