Answer:
Question 4. True - As when water is boiled the water molecules expand and this exapansion leads more amount of salt that can be dissolved in it.
Question 5. True - As solubility curves show how the solubility of a solute in a given solvent changes as the temperature changes.
Question 6. True - As the solubility of KNO3 increases more than six times between 0 and 50 degrees C.
Question 7. False - As the solubility curve indicates changes in temperature for solubility of substances.
