CHE 1302 Lecture Notes - Lecture 4: Freezing-Point Depression, Semipermeable Membrane, Molar Mass
Document Summary
Baker | che 1302 | summer 2017| lecture 4 | page 1. Properties of solutions that depend only on the quantity (concentration) of solute particles, not their identity. Kind of bizarre at first look: depends solely on concentration, doesn"t matter what compound you"re looking at, unlike melting point, weight, etc. Observation: adding non-volatile solute to a solvent always lowers its vapor pressure. Volatile - has a vapor pressure: solids or liquids that produce a small amount of vapor that can be detected, perfume, sharpies, moth balls, etc. Solvent molecules can pass through the semipermeable membrane in both directions. It lets the small solvent particles pass through but not larger solute particles. The concentration of solvent at the membrane is greater on the right-hand side so more solvent passes from right -> left than left -> right. Solute particles can"t get though and get in the way of solvent molecules on the left side.
