The solubility of KNO3 is 155 g per 100 g of water at 75°C and 38.0 g at 25°C. What mass (in grams) of KNO3 will crystallize out of solution if exactly 100 g of its saturated solution at 75°C is cooled to 25°C? The textbook answer key says the answer is 45.9 grams, but I need to know how to solve it. Please explain with steps how to solve this.

definition

                    entropy is a measure of the randomness or the extent of disorder of a chemical process.

                      enthalpy is a measure of the heat change of a reaction occurring at a constant pressure.

measurement units:

                        entropy is measured in joule per kelvin (jk⁻¹)   whereas enthalpy is measured in joule per mole (jmol⁻¹)

requirements:

                            entropy has no requirements or limits, and its change is measured by the division between the heat change of the chemical process and the temperature.

                              in contrast, enthalpy can only be related to the heat change of the reaction under standard conditions.

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.