III. Sự điện phân
Tích số tan trong nước của một số chất ở 250C Chất điện liPhương trình điện li K a và K b
AgCl AgCl ← → Ag+ + Cl- 1,1.10-11 AgBr AgBr ← → Ag+ + Cl- 6,3.10-13 AgI AgI ← → Ag+ + I- 1,5.10-16 AgCN AgCN ← → Ag+ + CN- 7.10-15 AgIO3 AgIO ← → Ag+ + IO3- 3,2.10-8 Ag2S Ag2S ← → 2Ag+ + S2- 5,7.10-51 Al(OH)3 Al(OH)3 ← → Al3+ + 3OH- 1,9.10-33 Al(OH)3 Al(OH)3 ← → H+ + (AlO2.H2O)- 1,1.10-15 As2S3 As2S3 ← → 2As3+ + 3S2- 4.10-29 (ở 180C) BaCO3 BaCO3 ← → Ba2+ + CO32- 7.10 -9 BaCO4 BaCO4 ← → Ba2+ + CrO42- 2,3.10-10 BaSO4 BaSO4 ← → Ba2+ + SO42- 1,08.10-10 Be(OH)2 Be(OH)2 ← → Be2+ + 2OH- 2,7.10-10 H2BeO2 H2BeO2 ← → H+ + BeO22- 2.10-30 Bi(OH)3 Bi(OH)3 ← → Bi3+ + 3OH- 1,3.10-31 (ở 180C) BiOCl BiOCl ← → Cl- + BiO+ 7.10-9 Bi2S3 Bi2S3 ← → 2Bi3+ + 3S2- 1,6.10-72 (ở 180C) CaCO3 CaCO3 ← → Ca2+ + CO32- 4,8.10-9 Ca(OH)2 Ca(OH)2 ← → Ca2+ + 2HO- 3,1.10-5 CaSO4 CaSO4 ← → Ca2+ + SO42- 6,26.10-5
CaSO4.2H- 2O CaSO4.2H2O ← → Ca2+ + SO42- + 2H2O 1,3.10-4 Ca3(PO4 )2
Ca3(PO4)2 ← → 3Ca2+ + 2PO43- 1.10-4 Cd(OH)2 Cd(OH)2 ← → Cd2+ + 2OH- 2,4.10-13 (ở 180C) Co(OH)2 Co(OH)2 ← → Co2+ + 2OH- 1,6.10-18 (ở 180C) Co(OH)3 Co(OH)3 ← → Co3+ + 3OH- 2,5.10-43 CoS CoS ← → Co2+ + S2- 3,1.10-23 Cr(OH)3 Cr(OH)3 ← → Cr3+ + 3OH- 6,7.10-31 Cr(OH)3 Cr(OH)3 ← → CrO2- + H++ H2O 9.10-17 CuCO3 CuCO3 ← → Cu2+ + CO32- 5,6.10-10 Cu(OH)2 Cu(OH)2 ← → Cu2+ + 2OH- 5,6.10-20 Cu2Cl2 CuCl2 ← → Cu22+ + 2Cl- 1,8.10-7 Cu2I2 Cu2I2 ← → Cu22+ + 2I- 1,1.10-12 Cu2S Cu2S ← → Cu22+ + S2- 2.10-47 (ở 180C) CuS CuS ← → Cu2+ + S2- 4.10-38 FeCO3 FeCO3 ← → Fe2+ + CO33 2,11.10-11 Fe(OH)2 Fe(OH)2 ← → Fe2+ + 2OH 4,8.10-16 (ở 180C) Fe(OH)3 Fe(OH)3 ← → Fe3+ + 3OH- 3,8.10-38 (ở 180C) FeS FeS ← → Fe2+ + S2- 3,7.10-19 Hg2Cl2 Hg2Cl2 ← → Hg22+ + 2Cl- 1,1.10-18 Hg2I2 Hg2I2 ← → Hg22+ + 2l- 3,7.10-29 Hg2O Hg2O + H2O ← → Hg22+ + 2OH- 1,6.10-23
HgO HgO + H2O ← → Hg2+ + 2OH- 1,7.10-26 Hg2S Hg2S ← → Hg22+ + S2+ 1,0.10-47
(ở 180C) HgS HgS ← → Hg2+ + S2- 4,0.10-53 (ở 180C) KClO4 KClO4 ← → K+ + ClO4- 1,07.10-2 Li2CO3 Li2CO3 ← → 2Li+ + CO32- 1,66.10-3 MgCO3.3H2O MgCO3.3H2O ← → Mg2+ + CO32- +
3H2O
1,0.10-5 MgS MgS ← → Mg2+ + S2- 2,0.10-15 Mg(OH)2 Mg(OH)2 ← → Mg2+ + 2OH- 5,5.10-12 MnCO2 MnCO2 ← → Mn2+ + CO32- 5,05.10-10 Mn(OH)2 Mn(OH)2 ← → Mn2+ + CO32- 4.10-14 (ở 180C) MnS MnS ← → Mn2+ + S2- 5,6.10-16 (ở 180C) Ni(OH)2 Ni(OH)2 ← → Ni2+ + 2OH- 1,6.10-14 NiS NiS ← → Ni2+ + S2- 3.10-21 (ở180C) PbCO3 PbCO3 ← → Pb2+ + CO32- 1,5.10-13 PbCl2 PbCl2 ← → Pb2+ + 2Cl- 1,7.10-5 PbBr2 PbBr2 ← → Pb2+ + 2Br- 6,3.10-5 PbI2 PbI2 ← → Pb2+ + 21- 8,7.10-9 PbCrO4 PbCrO4 ← → Pb2+ + CrO42- 1,77.10-14 PbO PbO + H2O ← → Pb2+ + 2OH- 5,5.10-16 PbS PbS ← → Pb2+ + S2- 1,1.10-29 PbSO4 PbSO4 ← → Pb2+ + SO42- 1,8.10-8
Pt(OH)2 Pt(OH)2 ← → Pt2+ + 2OH- 102-5 Sb(OH)3 Sb(OH)3 ← → Sb3+ + 3OH- 4,0.10-42 Sb2S3 Sb2S3 ← → 2Sb3+ + 3S2- 1.10-30 H2SiO3 H2SiO3 ← → HSiO3+ + H- 1.10-30 Sn(OH)2 Sn(OH)2 ← → Sn4+ + 4OH- 5.10-26 Sn(OH)4 Sn(OH)4 ← → Sn4+ + 4OH- 1..10-56 SnS SnS ← → Sn2+ + S2- 1.10-28 SrCO3 SrCO3 ← → Sr2+ + CO32- 9,42.10-10 SrSO4 SrSO4 ← → Sr2+ + SO42- 2,8.10-7 TeO(OH)2 TeO(OH)2 ← → TeO2+ + 2OH- 1.10-11 Te(OH)4 Te(OH)4 ← → Te4+ + 4OH- 7.10 - 53 (ở 180C) TiO(OH)
2
TiO(OH)2 ← → TiO2+ + 2OH- 1.10-30 ZnCO3 ZnCO3 ← → Zn2+ + CO32- 6.10-11 Zn(OH)2 Zn(OH)2 ← → Zn2+ + 2OH- 4.10-16 ZnS ZnS ← → Zn2+ + S2- 6,9.10-26
