BaSO(s)-Ba2(aq)+ SO(aq) Initial/(nol.L) 2.0×103 4.8×10-4 Aftermixing/(md.L) 2.0×10-3-4.8×10-4 0 Equlibrium/(molL)1.52x103+x X (1.52×103+x)x=1.1×1010 x is verysmall,,1.52x103+x≈1.52×103 x=7.3×108 c(S02)=7.3×10-8moL mBaS04)=(4.8×104-x)×50.0×233 ≈4.8×104×50.0×233=5.6g 3 2.0 10-  4 4.8 10- Initial/(mol L )  -1  3 10 (1.5 2 1 0 ) 1.1 1 0 - -  + x  x =  3 3 is very small 1.5 2 1 0 1.5 2 1 0 - - x ，  + x   3 4 2.0 1 0 4.8 1 0 - - After mixing/(mol L )  -  0 -1   + x -3 Equlibrium/(mol L ) 1.52 10 x -1  BaSO (s) Ba (aq) SO (aq) 2 4 2 4 + - + 4.8 1 0 5 0.0 233 5.6g 4     = - (BaSO ) (4.8 1 0 ) 5 0.0 233 4 4 =  -   - m x 2 8 1 (SO4 ) 7.3 1 0 mol L - - - c =   8 7.3 10- x = 