Question

at what temperature will you find more potassium nitrate(kno3) in 100 g of H2O . In other words at which temperature will you have a higher solubility: 10c , 20c , 50c , 85c ?

Answer 1

The answer to this question would be: 85c 
Solubility is influenced by the temperature of the molecule. Higher temperature will result in a higher solubility. That is why brewing using hot water will be easier than using cold water. Higher temperature also means higher reaction rate.