If a ppt forms it must be because Ksp is exceeded. The only slightly soluble material is the possibility of CaSO4. Therefore, you must determine Qsp for the solution and see if Ksp is exceeded.
(Na2SO4) in final solution is 0.004 x (100/600) = approx 6.67E-4
(CaCl2) in final solution is 0.050 x (500/600) = approx 0.042
So Qsp = (Ca^2+)(SO4^2-) = apprx 2.8E-5. Compare this Qsp with Ksp for CaSO4. If Ksp is exceeded (Ksp smaller than Qsp) a ppt will occur; otherwise, no ppt. You may want to go through the calculations again if it's close to make sure of the approximations. Bt the way, I have assumed that the solutions are additive in volume; i.e., 100 mL + 500 mL = 600 mL.
I have no idea how to go about this question, please help!
A clumsy chemist accidentally pours 100 mL of a 0.004 M Na2SO4 solution into a beaker containing 500 mL of 0.050 M CaCl2. Will a precipitate be formed? Explain your reasoning and/or show all calculations?
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