2. Objectives: -> Define: Colligative Properties -> Explain: Why a liquid's boiling point is elevated but its freezing point is depressed when a solute dissolves. ->Describe: How the magnitude of a colligative property depends on the amount of solute and on the chemistry of the dissolution process. ->Compare: and contrast the roles of emulsifiers and surfactants. ->Explain: What hard water is and why its occurrence makes detergents superior to soaps.
3. Vocab -> Boiling-point elevation: The difference between the boiling point of a solution and that of the pure solvent -> Freezing-point depression: The difference between the freezing point of a pure solvent and that of a solution -> Colligative Property: A physical property that is dependent on the number of solute particles present rather than on the identity of those particles -> Emulsion: Colloidal-sized droplets (100nm in diameter) of one liquid suspended in another liquid
4. Vocab. (continued) -> Emulsifier: A substance that stabilizes an emulsion by forming a layer between two immiscible liquids -> Soap: A sodium or potassium salt of a long-chain fatty acid -> Micelle: A spherical arrangement formed by molecules of fat substances in an aqueous environment -> Surfactant: A class of salts, valued for their cleansing properties. -> Detergent: A surfactant other than a soap
