chloride
Cl -
oxide
O 2-
hydroxide
OH -
nitrate
NO3 -
sulphate
SO4 2-
carbonate
CO3 2-
ammonium
NH4 +
potassium
K +
sodium
Na +
calcium
Ca 2+
magnesium
Mg 2+
aluminium
Al 3+
iron (ii)
Fe 2+
iron (iii)
Fe 3+
hydrogen
H +
copper
Cu 2+
silver
Ag +
zinc
Zn 2+
manganate (vii)
MnO4 -
chromate
CrO2 -
dichromate
Cr2O7 2-