In a laboratory, a student makes a solution by completely dissolving 80.0 grams of KNO3(s) in 100.0 grams of hot water. The resulting solution has a temperature of 60.°C. The room temperature in the laboratory is 22°C.
65 Classify, in terms of saturation, the type of solution made by the student. [1]
HIGHLIGHT TO SEE THE ANSWER
unsaturated NOTE= look at Table G KNO3 holds 115g at 60.°C |
66 Compare the boiling point of the solution at standard pressure to the boiling point of water at standard pressure. [1]
HIGHLIGHT TO SEE THE ANSWER
The boiling point of the solution at standard pressure is higher than the boiling point of waterat standard pressure. Water boils at a lower temperature. Link-Boiling point elevation |
67 Describe the direction of heat flow between the solution made by the student and the air in the laboratory. [1]
HIGHLIGHT TO SEE THE ANSWER
NOTE=Energy (heat) flows from hot to cold Heat flows from the solution to the air in the laboratory. The air gains heat from the solution. |
68 Describe a laboratory procedure that can be used to recover the solid solute from the aqueous solution. [1]
HIGHLIGHT TO SEE THE ANSWER
Gently heat the solution to evaporate the water until only solid KNO 3 remains.Boil off the water. Distillation |