水に対する溶解性
  NH4+ Na+ K+ Mg2+ Ca2+ Ba2+ Zn2+ Al3+ Fe2+ Fe3+ Pb2+ Cu2+ Ag+
O2- --- × × × × × ×
OH- × × △ × × × ---
Cl- ×
SO42- × ×
NO3-
CO32- × × × --- × --- × × ×
PO43- × × × × × × ×
CH3COO-