I. Introduction to Acids & Bases Ch. 19 – Acids & Bases

Review – Acid Nomenclature

Review – Naming Acids  HCl H2SH2S  H 2 SO 4  H 2 SO 3  HNO 3  HNO 2  HBr  Hydrochloric acid  Hydrosulfuric acid  Sulfuric acid  Sulfurous acid  Nitric acid  Nitrous acid  Hydrobromic acid

A. Properties  electrolytes  turn litmus red  sour taste  react with metals to form H 2 gas  slippery feel  turn litmus blue  bitter taste  vinegar, milk, soda, apples, citrus fruits  ammonia, lye, antacid, baking soda

B. Definitions HF H 3 PO 4 H 2 SO 4 H +  Monoprotic – an acid with one H + – an acid with more than one H +  Polyprotic – an acid with more than one H + Diprotic – an acid with 2 H +Diprotic – an acid with 2 H + Triprotic – an acid with 3 H +Triprotic – an acid with 3 H + monoprotic triprotic diprotic polyprotic

B. Definitions  Arrhenius HCl + H 2 O  H 3 O + + Cl – Acids contain hydrogenAcids contain hydrogen AcidsAcids form hydronium ions (H 3 O + ) in aqueous solution H HHHH H Cl OO – + acid

B. Definitions  Arrhenius Bases contain a hydroxide groupBases contain a hydroxide group BasesBases form hydroxide ions (OH - ) in aqueous solution NaOH  Na + + OH - base H2OH2O

B. Definitions  Brønsted-Lowry HCl + H 2 O  Cl – + H 3 O + AcidsAcids are proton (H + ) donors BasesBases are proton (H + ) acceptors conjugate acid conjugate base baseacid

B. Definitions  Brønsted-Lowry HBr + NaOH  NaBr + H 2 O Conjugate AcidsConjugate Acids are the result after a base accepts a hydrogen ion Conjugate BasesConjugate Bases are the result after an acid donates a hydrogen ion conjugate acid conjugate base baseacid

B. Definitions H 2 O + HNO 3  H 3 O + + NO 3 – CBCAAB H 2 O + NH 3  NH OH - CACB B A – can be an acid or a base  Amphoteric – can be an acid or a base

B. Definitions F - H 2 PO 4 - H2OH2O HF H 3 PO 4 H 3 O +  Give the conjugate base for each of the following: – an acid with more than one H +  Polyprotic – an acid with more than one H +

B. Definitions Br - HSO 4 - CO 3 2- HBr H 2 SO 4 HCO 3 -  Give the conjugate acid for each of the following:

B. Definitions  Lewis AcidsAcids are electron pair acceptors BasesBases are electron pair donors Lewis base Lewis acid

C. Strength  Strong Acid/Base 100% ionized in water strong electrolyte - + HCl HNO 3 H 2 SO 4 HBr HI HClO 4 NaOH KOH RbOH CsOH Ca(OH) 2 Ba(OH) 2

C. Strength  Weak Acid/Base does not ionize completely weak electrolyte - + HF CH 3 COOH H 3 PO 4 H 2 CO 3 HCN NH 3

Ch. 19 – Acids & Bases II. pH (p. 644 – 658)

A. Ionization of Water H 2 O + H 2 O H 3 O + + OH - Self-Ionization of Water

Ion Product Constant for Water For all aqueous solutions, the product of the hydrogen-ion concentration and the hydroxide-ion concentration equals 1.0 x The ion production of water, K w = [H 3 O + ][OH – ] Pure water contains equal concentrations of H + and OH – ions, so [H 3 O + ] = [OH – ] A. Ionization of Water K w = [H 3 O + ][OH - ] = 1.0 

A. Ionization of Water  Find the hydroxide ion concentration of 3.0  M HCl. [H 3 O + ][OH - ] = 1.0  [3.0  ][OH - ] = 1.0  [OH - ] = 3.3  M HCl → H + + Cl  M

A. Ionization of Water  Find the hydronium ion concentration of 1.4  M Ca(OH) 2. [H 3 O + ][OH - ] = 1.0  [H 3 O + ][2.8  ] = 1.0  [H 3 O + ] = 3.6  M Ca(OH) 2 → Ca OH  M 2.8  M

pH = -log[H 3 O + ] B. pH Scale 0 7 INCREASING ACIDITY NEUTRAL INCREASING BASICITY 14 pouvoir hydrogène (Fr.) “hydrogen power”

B. pH Scale pH of Common Substances

B. pH Scale pH = -log[H 3 O + ] pOH = -log[OH - ] pH + pOH = 14

B. pH Scale  What is the pH of M HNO 3 ? pH = -log[H 3 O + ] pH = -log[0.050] pH = 1.30 Acidic or basic? Acidic

B. pH Scale  What is the pH of M Ba(OH) 2 ? [OH-] = M pOH = -log[OH - ] pOH = -log[0.100] pOH = 1.00 pH = Acidic or basic? Basic

B. pH Scale  What is the molarity of HBr in a solution that has a pOH of 9.60? pH + pOH = 14 pH = 14 pH = 4.40 Acidic pH = -log[H 3 O + ] 4.40 = -log[H 3 O + ] = log[H 3 O + ] [H 3 O + ] = 4.0  M HBr

C. pH Worksheet #6 A swimming pool has a volume of one million liters. How many grams of HCl would need to be added to that swimming pool to bring the pH down from to ? (Assume the volume of the HCl is negligible) 7 = -log[H+] -7 = log[H+] [H+] = 1 x M -4 = log[H+] [H+] = 1 x M = 100 mol H+ 1,000,000L Sol’n 1x10 -4 mol H+ 1 L soln = 0.1 mol H+ 1,000,000L Sol’n 1x10 -7 mol H+ 1 L soln

C. pH Worksheet #6 100 mol H+ – 0.1 mol H+ = 99.9 mol HCl = 3642 g HCl 99.9 mol HCl g HCl 1 mol HCl A swimming pool has a volume of one million liters. How many grams of HCl would need to be added to that swimming pool to bring the pH down from to ? (Assume the volume of the HCl is negligible)

D. pH Sig Figs  For the pH, the number of sig figs is shown by the # of decimal places [H+] = 2.26 x M =>  For the molarity from the pH, check decimal places in the pH pH = 4.25 => pH = x M