An aqueous solution contains an unknown concentration of Ba^(2+) when 50 mL of a 1 M solution of Na_(2)SO_(4) is added, BaSO_(4) just begins to precipitate. The final volume is 500mL. The solubility product of BaSO_(4) is 1xx10^(-10). What is the original concentration of BA^(2+)

An aqueous solution contains an unknown concentration of Ba^(2+) when

1.	An aqueous solution contains an unknown concentration of Ba^(2+) when 50 mL of a 1 M solution of Na_(2)SO_(4) is added, BaSO_(4) just begins to precipitate. The final volume is 500mL. The solubility product of BaSO_(4) is 1xx10^(-10). What is the original concentration of BA^(2+)
Answer» `2xx10^(-9)M` `1.1xx10^(-9)M` `1.0xx10^(-10)M` `5XX10^(-9)M` Solution :`Ba^(+2)+SO_(4)^(2-)hArrunderset(ppt)(BaCo_(4(s)))` FINAL CONC. Of `[SO_(4)^(2-)]=(MV_(1))/(V_(1)+V_(2))=(1xx50)/(500)=0.1M` Final conc. Of `[Ba^(+2)]when BaSO_(4)` start PRECIPITATING `K_(SP)=Q_(SP)=[Ba^(+2)][SO_(4)^(2-)]` `10^(-10)=[Ba^(+2)](0.1M)` `[Ba^(+2)]=10^(-9)M` initial conc. `[Ba^(+2)],` initial volume was `=500-50=450` ml `M_(1)=(M_(2)V_(2))/(V_(1))=(10^(-9)xx500)/(450)` `M_(1)=1.1xx10^(-9)M.`