you made up a standard solution of calcium sulfate (CaSO4). the temperature is 25C. you then add 5.00*10^-3 odium sulfate (Na2SO4). Calculate the concentrations of calcium and sulfate after equilibrium is reached? The pKs of CaSO4 is 4.58.

Answer 1

CaSO4 ==> Ca^+2 SO4^-2
Ksp = (Ca^+2)(SO4^-2) = 4.58E?? (you had better look up the Ksp because 4.58 can't possibly be correct.)
You then add 5.00*10^-3 WHAT of Na2SO4.
Take care of the errors in this and I'll get back to it.

Answer 2

the pKs is correct. If you 10 to the negative power of pKs you get the Ks. I'm having a problem witht this problem as well. Any help? And yes, you add 5*10^-3 of Na2SO4.