Question

The Ksp for MgCO3 is 6.8 x 10-6. To produce 100 mL of a saturated solution, ___ grams of MgCO3 would be required.

Answer 1

Answer:

Ksp of MgCO3= 6.8 * (10)-6

MgCO3 ==>Mg2+ + CO32-

Ksp = (Mg2+)([CO3]2-)

If you let x = solubility of MgCO3,  

then x = (Mg2+) and x = ([CO3]2-).  

Substitute and solve for x = solubility MgCO3.

That will be mols/L. Convert to mols in 100 mL and then resultant into grams.