Step-by-step explanation:
The amount of KNO3 that will precipitate out of a saturated solution upon cooling depends on the solubility of KNO3 at the two different temperatures. The solubility of a substance in a solvent is temperature-dependent, meaning that the solubility of a substance may increase or decrease with changes in temperature.
To determine the amount of KNO3 that will precipitate, we need to know the solubility of KNO3 at 50°C and 20°C. This information is usually available in a solubility table or from experimental data. If we know the solubility of KNO3 at 50°C and 20°C, we can calculate the amount of KNO3 that will precipitate by comparing the amount of KNO3 in the saturated solution at 50°C with the maximum amount that can be dissolved at 20°C.
Without knowing the specific solubility values, it is not possible to accurately determine the amount of KNO3 that will precipitate upon cooling.