Aqueous reactions and solution stoichiometry Aqueous SolutionsAqueous Solutions Acid and BasesAcid and Bases Precipitation ReactionsPrecipitation Reactions Acid-Base ReactionsAcid-Base Reactions Oxidation-Reduction ReactionsOxidation-Reduction Reactions ConcentrationConcentration Solution StoichiometrySolution Stoichiometry

Solution : A homogeneous mixture of two or more components, consists of two component types –Solvent: major component –Solute: component in the lesser extent Aqueous Solutions : –Ionic compounds –Molecular compounds Electrolyte : –Strong electrolytes: strong acid/base, soluble ionic compounds –Weak electrolytes: weak acid/base –Nonelectrolytes Solutions

Acid and Base Acid - a compound that increases [H + ] in water ex. HNO 3 H + (aq) + NO 3 - (aq) –Strong acid: HCl, HBr, HI, HNO 3, H 2 SO 4, HClO 4, HClO 3 –Weak acid Base - a compound that increases [OH - ] in water, proton acceptor –Strong base: hydroxide of IA, IIA, LiOH, NaOH, KOH, RbOH, CsOH, Ca(OH) 2, Sr(OH) 2, Ba(OH) 2 –Weak base H2OH2O

Precipitate –Insoluble product that is formed from a reaction is solution Solubility: solubility rule, Table 4.1, p. 118 Exchange reaction (metathesis) AX+BY --> AY + BX * Exchange reaction will occur when one of the products is insoluble solids, gas, weak or nonelectrolyte Ionic Equation –Molecular equation –Ionic equation Complete ionic equation, net ionic equation Precipitation Reactions

Neutralization reaction Acid + Base --> Salt + H 2 O Ex. HCl (aq) + NaOH (aq) --> NaCl (aq) + H 2 O (l) Acid-base reaction with gas formation Ex HCl (aq) + NaHCO 3 (aq) --> NaCl (aq) +H 2 O (l) + CO 2 (g) Acid-Base Reactions

Redox reactions: electrons are transferred between reactants –Oxidation: lose electron –Reduction: gain electron Oxidation state/oxidation number –Assigning oxidation number Element Monatomic ion Nonmetal in compounds All other Displacement reaction A + BX --> AX + B Activity Series: Table 4.5, P.131 Oxidation-Reduction Reactions

Concentration: measures how much solute is in a solution Molarity, M: unit in mol/L Dilution M conc x V conc = M dil x V dil Molarity, M = no of moles of solute total volume solution in L Concentration

Procedure: Fig 4.18, P. 139 –Start with balancing equation –Work with moles –Convert to concentration or volume Solution Stoichiometry

Titration : A method to determine the amount of a substance in solution Standard solution (titrant): a solution of known concentration Equivalence point : when just enough titrant is added to the solution Indicator : a substance changes color at the end point End point : when indicator changes color Acid-base titration: to determine the concentration of unknown solution Titration