Unit 14: Solutions & Equilibrium NO2 ⇄ N2O4

Unit 14: Solutions & Equilibrium A. Solution Formation Solution - homogeneous mixture Solute - substance being dissolved Solvent – dissolving medium (dissolver) (present in greatest amount)

A. Solution Formation Types of Solutions: Solute Solvent Example Gas Air (O2 & CO2 in Nitrogen) Liquid Water in Air CO2 in Soda Vinegar (acetic acid in water) Solid Salt in water Stainless Steel (Cr & Ni in Iron) *Known as Alloys

Solubility in 100 g of Water at 20oC A. Solubility Solubility maximum mass of solute that will dissolve in a given amount of solvent at a given temperature Solubility in 100 g of Water at 20oC Compound Solubility (g) Table Salt (NaCl) 36.0 g Baking Soda (NaHCO3) 9.6 g Table Sugar (C12H22O11) 203.9 g (0.62 mol) (0.11 mol) (0.59 mol)

less solute than max dissolved more than max solute dissolved B. Solubility UNSATURATED less solute than max dissolved SATURATED max solute dissolved SUPERSATURATED more than max solute dissolved concentration

less solute than max dissolved more than max solute dissolved B. Solubility UNSATURATED less solute than max dissolved SATURATED max solute dissolved SUPERSATURATED more than max solute dissolved concentration

less solute than max dissolved more than max solute dissolved B. Solubility UNSATURATED less solute than max dissolved SATURATED max solute dissolved SUPERSATURATED more than max solute dissolved concentration

less solute than max dissolved more than max solute dissolved B. Solubility UNSATURATED less solute than max dissolved SATURATED max solute dissolved SUPERSATURATED more than max solute dissolved concentration

Why does stuff dissolve? (also, Ionic bonds when ionic compounds dissolve…) IMAFs between solute–solute solvent–solvent must break Greater solubility: stronger IMAFs with solute–solvent IMAFs between solute–solvent must form

B. Solution Formation Electrolyte: forms ions to conduct in solution - + salt NaCl - + sugar C12H22O11 Strong Electrolyte Non-Electrolyte ALL ions from dissolved ionic compounds ALL molecules from dissolved molecular compounds

To point out there are weak electrolytes: Strong electrolytes ionize completely (100%), while weak electrolytes ionize only partially (usually on the order of 1–10%). *Both strong and weak still dealing with ionic compounds dissolving, though.

Quick Quiz! 1) Compounds that partially dissociate (or ionize) into solutions of ions and molecules that partially conduct are … A) non-electrolytes B) weak electrolytes C) strong electrolytes