Chem 1160 Exam 4 Review WITH COMPLETE SOLUTIONS 2023

Factors that Influence Solubility: Addition of a common ion Lowers the solubility of ionic compounds by contributing an ion to the equilibrium. 00:07 01:42 Factors that Influence Solubility: Adding Acid If the anion of the ionic compound is a conjugate base of a weak acid, then the ionic compound would become more soluble. The anion is removed from the solubility equilibrium through a reaction with H+. If the anion of the ionic compound is a conjugate base of a strong acid (Cl-, Br-, I-, NO31-, ClO41-, SO42-), then adding acid would not increase the solubility of the ionic compound (no effect). Factors that Influence Solubility: Adding base (ligands) Addition of Ligands (Lewis Bases) increases the solubility of ionic compounds by removing the metal cations through a reaction with the ligand. Qsp = Ksp ??? the solution is saturated Qsp Ksp ??? precipitate forms Qsp Ksp ??? No precipitate forms Entropy is a measure of _____________. Disorder/Disorganization Entropy formula: S = k ln(W) "S"- entropy "k"- Boltzman's constant "W"- number of equivalent energy states If a system becomes more disorderly, gains more equivalent energy states or spatial arrangements, then ______. ΔSᴼ 0 If a system becomes more orderly, loses equivalent energy states or spatial arrangements, then _____. ΔSᴼ 0 Standard Molar Entropy Change ΔSᴼrxn = ΣnSᴼ(products) - ΣmSᴼ(reactants) ....Products-Reactants 00:04 01:42 Gibbs Free Energy ΔG = ΔH - TΔS ΔG = ΔH - TΔS: ΔG 0 Process is spontaneous ΔG = ΔH - TΔS: ΔG 0 Process is non-spontaneous ΔG = ΔH - TΔS: ΔG = 0 Process is at equilibrium ΔH (-) & ΔS(+) Spontaneous at all temperatures ΔH (+) & ΔS(-) Non-spontaneous at all temperatures ΔH (-) & ΔS(-) Spontaneous at "lower" temperatures and Non-spontaneous at "higher" temperatures ΔH (+) & ΔS(+) Spontaneous at "higher temperatures and Non-spontaneous at "lower" temperatures Cross-over Temperature Tcross-over = ΔH/ΔS