例6: 0.02 mol/LBaCl,2和H2SO,溶液等浓度混合, 问有无BaSO,沉淀析出? 解:己知KBmo)=11x1010,K2=1.0×102 CH,so,=[HS04]+[S0] Ka2 令602=04=} 10-2 CHS 。[H]+K2 102+102=0.5 S0]=Cn,so,0-002 ×0.5=5×10-3ol/L 2 而[Ba2]=9 =002=1.0×10-mol/L 2 [Ba2+1[S0]=1.0×10-2×5.0×103=5.0×105>1.1×1010 故有BaSO,沉淀析出 2024/10/12024/10/1 例6: ▪ 0.02mol/LBaCl2和H2SO4溶液等浓度混合, 问有无BaSO4沉淀析出? 解: 2 2 10 ( ) 1.1 10 1.0 10 4 − − 已知KSP BaSO = ,Ka = [ ] [ ] 2 4 4 2 4 − − CH SO = HSO + SO 0.5 10 10 10 [ ] [ ] 2 2 2 2 2 2 4 2 4 2 4 = + = + = = − − − + − − a a H SO SO H K K C SO SO C mol L H SO SO 0.5 5 10 / 2 0.02 [ ] 2 3 4 2 4 2 4 − − = − = = 2 2 3 5 1 0 4 2 [ ][ ] 1.0 10 5.0 10 5.0 10 1.1 10 + − − − − − Ba SO = = 故有BaSO4 沉淀析出 Ba 1.0 10 mol / L 2 0.02 [ ] 2+ −2 而 = =