Precipitation pH range of certain metal oxides and hydroxides


 
Element Metal oxide or hydroxide Precipitation pH Highest precip Lowest Precip
Niobium Nb 5+ 1 to 10 10 1
Tantalium Ta 5+ 1 to 10 10 1
Hafnium Hf 4+ 6 to 7 7 6
Indium In 3+ 6 to 13 13 6
Iridium Ir 4+ 6 to 8 8 6
Rhenium Re 3+ 6 and up 1N 14 6
Thorium Th 4+ 6 and up 1N 14 6
Zirconium Zr 4+ 6 to 7 7 6
Aluminum Al 3+ 7 to 8 8 7
Antimony Sb 3+ 7 to 8 8 7
Antimony Sb 5+ 7 to 8 8 7
Beryllium Be 2+ 7 to 8=7F 8 7
Bismuth Bi 3+ 7 and up 1N 14 7
Cadmium Cd 2+ 7 and up 1N 14 7
Chromium Cr 3+ 7 and up 1N 14 7
Copper Cu 2+ 7 and up 1N 14 7
Gallium Ga 3+ 7 to 8 8 7
Gold Au 3+ 7 to 8 8 7
Iron Fe 2+ 7 and up 1N 14 7
Lead Pb 2+ 7 to 8 8 7
Manganese Mn 4+ 7 and up 1N 14 7
Osmium Os 4+ 7 to 8 8 7
Paladium Pd 2+ 7 to 8 8 7
Paladium Pd 4+ 7 to 8 8 7
Platinum Pt 2+ 7 to 8 8 7
Rhodium Rh 3+ 7 to 8 8 7
Ruthenium Ru 3+ 7 and up 1N 14 7
Tin Sn 2+ 7 to 8 8 7
Tin Sn 4+ 7 to 8 8 7
Vanadium V 4+ 7 to 8 8 7
Vanadium V 5+ 7 to 8 8 7
Zinc Zn 2+ 7 to 8 8 7
Cobalt Co 2+ 8 and up 1N 14 8
Manganese Mn 2+ 8 and up 1N 14 8
Mercury Hg 1+ 8 and up 1N 14 8
Mercury Hg 2+ 8 and up 1N 14 8
Nickel Ni 2+ 8 and up 1N 14 8
Scandium Sc 3+ 8 and up 1N 14 8
Titanium Ti 3+ 8 and up 1N 14 8
Titanium Ti 4+ 8 and up 1N 14 8
Copper Cu 1+ 9 and up 1N 14 9
Magnesium Mg 2+ 9 and up 1N 14 9
Silver Ag 1+ pH 9 and up 1N 14 9
Thallium Tl 3+ 9 and up 1N 14 9

THE pH OF NATURAL MEDIA AND ITS RELATION TO THE PRECIPITATION OF HYDROXIDES


 
pH Precipitation of hydroxides Natural media pH
11 Magnesium 11
10 Magnesium Alkali soils 10
9 Bivalent Manganese Seawater 9
8 Bivalent Manganese Seawater 8
7 Bivalent Iron River water 7
6 Zinc Copper Rain water 6
5 Aluminum 5
4 Peat water 4
3 Triavalent iron Mine waters 3
2 Triavalent iron Acid thermal springs 2
1 Acid thermal springs 1