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AIM: How do colligative properties affect solubility of substances?. UNIT 3 SOLUTIONS AND GASES 3.6 How do we calculate the concentration of a solution?. DO NOW: Define the following words: Solute Solvent Solution. April 27, 2011. COLLIGATIVE PROPERTIES. What are they?
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AIM:How do colligative properties affect solubility of substances? UNIT 3 SOLUTIONS AND GASES3.6 How do we calculate the concentration of a solution? DO NOW: Define the following words: Solute Solvent Solution April 27, 2011
COLLIGATIVE PROPERTIES • What are they? properties that depends on the number of solute particles present in a solution. Colligative properties include vapor pressure, boiling point, freezing point, and osmotic pressure.
LAB Directions: • Access EXPLORELEARNING.COM • USERNAME: asphigh • PASSWORD: asphigh • Press on CRII • Choose Colligative Properties Lab • Start you lab
YOU WILL • Measure the freezing point and boiling point of a solution. • Observe how adding a solute changes the vapor pressure, boiling point, and freezing point of a solution. • Relate the effects of a solute to its concentration. • Observe and predict how a solute will dissociate in water. • Relate the effects of a solute to the way it dissociates.
DISCUSSION QUESTIONS • Which solute has the greatest effect on the vapor pressure, boiling point, and freezing point of the solution? Why? • How does the chemical formula of an ionic compound relate to the number of particles it dissociates into when dissolved in a solution? • At the molecular level, what is happening when water boils? How would this process be affected by the addition of a solute that does not evaporate? [The answer to this question as well as the next two questions is discussed in the Scientific Background below.] • At a molecular level, what is happening when water freezes? How would this process be affected by the addition of a solute that does not evaporate? • At a molecular level, what is happening during osmosis? How would this process be affected by the addition of more solute?
INDEPENDENT PRACTICE • Complete the Independent Practice • PLACE the lab in the CHEMICAL REACTIONS BIN • YOU HAVE UNTIL FRINDAY, APRIL 29, 2011 TO HAND IN: • WORK FROM UNIT 6 (before the break) • any missing labs • Test corrections