CHM 104 1st Edition Lecture 13 Outline of Last Lecture I Acids and Bases II Arrhenius Definition III Br nsted Lowry Definition Outline of Current Lecture IV Acid Strength and the Ionization Constant Current Lecture Strong Acids Completely ionizes in reaction with H2O HCl aq HCl l H3O aq Cl aq Ionized forms Example HCl aq HCl l H3O aq Cl aq I 0 10 M l F 0 l 0 0 0 10 M 0 10 M Other Strong Acids H2SO4 1st proton only HBr HNO3 HI HClO4 perchloric Weak Acids Weak acids only partially ionize in reaction with H2O Best thought of as an equilibrium HA aq H2O l H3O aq A aq These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute The behavior ranges from ionizing very very little to almost 100 Example HF aq H2O l H3O aq F aq Mostly intact HF only small amount ionizes Strength depends on how strongly the H is bound to the acid H A The stronger this bond is the weaker the acid will be Common Weak Acids HF Hydrofluoric acid HC2H3O2 Acetic acid HCHO2 Formic acid Polyprotics H2SO3 Sulfurous acid H2CO3 Carbonic acid H3PO4 Phosphoric acid Strong H2SO4 aq H2O l HSO4 aq H3O aq Weak HSO4 aq H2O l SO42 aq H3O aq Don t Confuse Strength and Concentration Strength fraction of acid that ionizes to generate H3O fraction of base that ionizes to generate OH Concentration Amount of substance amount of acid or amount of base Strength of Acid and its Conjugate Base HCl aq H2O l H3O aq Cl aq Strong Acid HF aq Very Weak Base H2O l H3O aq Weak Acid F aq Weak Base Strength Quantified by Acid Ionization Constant Ka HA aq H2O l H3O aq A aq Typical Ka s for weak acids range from 10 2 to 10 10 Formic Acid Ka 1 8 x 10 4 Hydrocyanic Acid Ka 4 9 x 10 10 HCN is a weaker acid than Formic HCHO2 CN is a stronger base than CHO2 Acid Base Behavior of Water Water can act as an acid OR a base
View Full Document
Unlocking...