posted by shahad .
if BaSo4 was precipitated in solution contain 0.012 M NaCl and 0.002 M BaCl2 .calculate the sulfate concentration which is sufficient for saturate the solution with BaSo4 , if you now that the Ksp for BaSo4 equal to 1*10^-10 .
BaSO4 ==> Ba^+2 + SO4^-2
Ksp = (Ba^+2)(SO4^-2) = 1E-10
Plug in 0.002M for (Ba^+2) [from the BaCl2] and solve for sulfate ion. This assumes you are not to make a correction for the activity coefficients and work with straight molarity. Otherwise you must calculate the activity coefficients and correct for molarities and Ksp.
ha ha doing the same problem right now