How can the value of ksp be related to the molar solubility of a compound? view available hint(s) how can the value of ksp be related to the molar solubility of a compound? when a common ion is present, the solubility of the compound decreases, and this is reflected in a lower value of ksp. the square of a compound's molar solubility equals the value of ksp for the compound. the value of ksp equals the concentration of the compound in a saturated solution, which can be converted to the molar solubility using the molar mass. the molar solubility can be used to calculate the concentrations of ions in solution, which in turn are used to calculate ksp.