Chemistry 178 Exam 2 Review

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Chemistry 178 Leader: Alarm Cho Exam 2 Review Course: Chem 178 Supplemental Instruction Instructor: John Verkade Iowa State University Date: Oct. 20, 2009 Concepts - Subsequent Ka’s for different Chapter 16 – Acid-Base Equilibria protons released Acids and Bases Weak Bases - Definitions: - Base Dissociation Constant Bronsted-Lowry (protons) (Kb) Arrhenius ([H+],[OH-]) - Relationship b/t the constants Conjugate Acid, Base pairs and base strengths Amphiprotic (i.e. Water) - Calculating pH of basic Relative Strengths of Acids solution from Kb & visa versa - Strong Acid Relationship between Ka and Kb - Weak Acid - Ka × Kb = Kw - Negligible Acid - pKa + pKb = pKw = 14 - Equilibrium in Acid-Base Acid-Base properties of salt Reaction solutions Autoionization of Water - Effects of cations and anions - Amphoteric (i.e. water) on pH. (p.695-697 in txt bk) - Ion Product Constant of Factors affecting Acid strength water (Kw) - Polarity of bond The pH scale - Bond strength - - Stability of conjugate base - Pure water pH = 7 Binary acid strengths - Acidic pH >7 - Across the row, down a - Basic pH < 7 column - Oxyacid strengths - p{ } means = ? - Proportional to the number of - pH + pOH = 14 oxygens Measuring pH – litmus paper, - When same number of indicator, pH meter oxygen and OH groups, then Strong Acids and Bases stronger with stronger - Know the strong acid and electronegativity of central Y base list atom. - Strong acids and bases Carboxylic Acid dissociate completely. - Resonance structure - Weak Acids Lewis Acids and Bases - Acid Dissociation Constant - Accept/Donate electron pairs (Ka) - Hydrolysis of metal ions - Relationship b/t the constants Chapter 17—Additional Aspects of and Aqueous Equilibria - acid strengths Common Ion Effect - Calculating pH from Ka & - Ties into Le Chatlier’s visa versa Principle - Calculating percent Buffered solutions ionization - Definition Polyprotic Acids Supplemental Instruction 1060 Hixson-Lied Student Success Center 294-6624 www.si.iastate.edu - Henderson-Hasselbalch Equation (calculating pH of buffer) - pH Range, Buffer capacity - Addition of strong acid to buffers. - Addition of strong base to buffers. - Problem solving strategy— diagram from notes. Acid-Base Titrations - Understand the titration curve. It can serve as a flow chart when solving titration problems. - Strong acid-strong base - Weak acid-strong base - Weak base-strong acid - Titration curve and the strength of weak acids - Titration curve of polyprotic acids Solubility Equilibria - Solubility product - Solubility Factors that affect solubility - Common ion effect - pH - Complex ions - Amphoterism - Precipitate formation (Q vs. Ksp) - Selective precipitation of ions Know your demonstrations and equations! Also know how to do homework problems and all the quiz problems. If you want more detail in the subjects listed on the review sheet, please refer to the notes or the previous SI worksheets. .

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