When KNO_3 dissolves, is the process endothermic or exothermic?

Question

Hint: The solubility of KNO_3 increases as temperature increases.

Answer 1

The process of dissolving Potassium Nitrate (KNO3) in water is endothermic (delta H > 0), energy flow into the system from the surroundings.
The fact that this process is endothermic is quite evident to anyone who has actually carried out the procedure, the resulting solution's temperature can drop very fast as more and more KNO3 dissolved.