The solubility of potassium nitrate is 13 g per 100. mL of water at 0 oC and 246 g per 100. mL of water at 100.oC. A quantity of 246 g of potassium nitrate is dissolved in 100. mL of water at 100. oC and the solution is cooled to 0 oC. What percentage by mass of the KNO3 crystallizes at 0oC?