valencies of common ions

• Hydrogen


  H+
• Sodium


  Na+
• Potassium


  K+
• Silver 


  Ag+
• Lithium


  Li+
• Copper (I)

  Cu+
• Ammonium


  NH4+
• Magnesium


  Mg+2
• Calcium


  Ca+2
• Barium


  Ba+2
• Iron (II)


  Fe+2
• Cobalt


  Co+2
• Zinc


  Zn+2
• Lead (II)


  Pb+2
• Tin (II)


  Sn+2
• Copper (II)


  Cu+2
• Aluminium


  Al+3
• Chromium (III)


  Cr+3
• Iron (III)


  Fe+3
• Tin (IV)


  Sn+4
• Lead (IV)


  Pb+4
• Fluoride


  F-
• Chloride


  Cl-
• Bromide


  Br-
• Iodide


  I-
• Hydroxide


  OH-
• Nitrate


  NO3-
• Nitrite


  NO2-
• Ethanate


  CH3COO-
• Hydrogencarbonate


  HCO3-
• Hydrogensulfate


  HSO4-
• Permangate


  MnO4-
• Oxide


  O-2
• Sulfide


  S-2
• Sulfate


  SO4-2
• Sulfite


  SO3-2
• Carbonate


  CO3-2
• Chromate


  CrO4-2
• Dichromate


  Cr2O7-2
• Nitride


  N-3