CHEM 1220 Lecture Notes - Lecture 1: Calcium Chloride, Joule, Ammonium Nitrate
Document Summary
Solutions: do not settle, homogenous mixture of two or more substances, solutions are possible in all phases, miscible: components mix or dissolve in all proportions (similar. Forces) polarity: immiscible: components form multiple layers (depends on, solvation: interaction between solute and solvent molecules, hydration: water in the solvent, solvent: present in greater amount, solute: present in the smaller quantity 1. For solution to occur, intermolecular forced must be comparable. Energetics: solute-solute, solute-solvent, solvent-solvent, mix calcium chloride and water: Cacl2 (s) > ca2+ (aq) + 2cl- (aq) + heat (exothermic delta h < 0: mix ammonium nitrate and water: Nh4no3 (s) > nh4+ (aq) + no3- (aq) (endothermic delta h > 0) Delta hsolution = delta h1 + delta h2 + delta h3: delta h1 = energy required to separate solute. Must be positive (endothermic: delta h2 = energy required to separate solvent. Must be positive (endothermic: delta h3 = energy gained from solute-solvent attraction (mixing)
