<p> Colligative Properties Name:</p><p>Colligative properties: physical properties of a solution that depend upon the amount of solute in the solvent.</p><p> a. Vapor Pressure Lowering: Some solutes attract the water molecules so the vapor pressure is lowered. The more solute, the lower the VP</p><p> b. Boiling Point Elevation: Since Boiling Point is dependent of VP, and a solute lowers the VP, then the Boiling Point increases.</p><p>^Tb= kb x m for ionic solutions ^Tb= kb x m x i</p><p> o kb= freezing point constant for solvent. Water is .512 C/m see text for more</p><p> i= number of ions formed when an ionic compound dissociates. NaCl---> Na+ + Cl- i= 2</p><p> m= molality</p><p> c. Freezing Point Lowering: A solute in a solvent interfers with crystal structure so the solvent freezes at a lower temperature.</p><p> all equations are analogous to ^Tb. </p><p> o Kf for water is -1.86 C/m</p><p>. </p><p>Problems:</p><p>1. Calculate the boiling temperature for a solution which contains 1.5mole of sodium iodide, NaI, dissolved in 1.25 kg of water.</p><p>2. Calculate the freezing point of a solution composed of 23.4 grams of Calcium Fluoride dissolved in 175 grams of water.</p><p>3. Calculate the molality of an aqueous solution(not ionic), that has a boiling point of 105.0oC. 4. At what temperature will a 3.0m solution of sodium fluoride freeze?</p><p>5. Calculate the boiling temperature for a solution which contains .325 mole of calcium phosphate dissolved into 240.0 grams of water.</p><p>6. What is the value of i for the following solutes? a. Na2SO4 b. KOH c. Al2(SO4)3 d. CH3OH </p><p>7. A solution is made by dissolving 25.0 grams of sodium sulfate in .500 kg of water. What are the boiling point and Freezing points of this solution. </p><p>8. What is the GFM of a substance that lowers the freezing point of water by 1.12o when 20 grams are put into 200 grams of water. ( not ionic)</p><p>9. What is the GFM of a substance that raises the boiling point to 103oC when 3.5 grams are put into 150 grams of water? ( not ionic )</p>