what is solubility? what is solubility? the solubility is the amount of solute that is necessary to prepare an unsaturated solution. the solubility is the amount of solvent that is necessary to prepare an unsaturated solution. the solubility is the amount of solvent that is necessary to prepare a supersaturated solution. the solubility is the amount of solute that is necessary to prepare a supersaturated solution. the solubility is the amount of solvent that dissolves in a specified amount of solute. the solubility is the amount of solute that dissolves in a specified amount of solvent.