1 / 23

I. Introduction to Acids & Bases

Ch. 19 – Acids & Bases. I. Introduction to Acids & Bases. electrolytes  electrolytes. A. Properties. ACIDS. BASES. bitter taste. sour taste. turn litmus red. turn litmus blue. react with metals to form H 2 gas. slippery feel. vinegar, milk, soda, apples, citrus fruits.

nishan
Download Presentation

I. Introduction to Acids & Bases

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ch. 19 – Acids & Bases I. Introduction toAcids & Bases

  2. electrolytes electrolytes A. Properties ACIDS BASES • bitter taste • sour taste • turn litmus red • turn litmus blue • react with metals to form H2 gas • slippery feel • vinegar, milk, soda, apples, citrus fruits • ammonia, lye, antacid, baking soda

  3. H H – + O O Cl Cl H H H H B. Definitions • Arrhenius • Acids contain hydrogen • Acidsform hydronium ions (H3O+) in aqueous solution HCl+ H2O  H3O+ + Cl– acid

  4. B. Definitions • Arrhenius • Bases contain a hydroxide group • Bases form hydroxide ions (OH-) in aqueous solution H2O NaOH Na+ + OH- base

  5. conjugate base conjugate acid B. Definitions • Brønsted-Lowry • Acidsare proton (H+) donors • Bases are proton (H+) acceptors HCl + H2O  Cl– + H3O+ acid base

  6. conjugate base conjugate acid B. Definitions • Brønsted-Lowry • Conjugate Acidsare the result after a base accepts a hydrogen ion • Conjugate Bases are the result after an acid donates a hydrogen ion HBr + NaOH  NaBr + H2O acid base

  7. B. Definitions H2O + HNO3 H3O+ + NO3– B A CA CB H2O + NH3 NH4+ + OH- B CA CB A • Amphoteric – can be an acid or a base

  8. F - H2PO4- H2O HF H3PO4 H3O+ B. Definitions • Give the conjugate base for each of the following: • Polyprotic – an acid with more than one H+

  9. Br - HSO4- CO32- HBr H2SO4 HCO3- B. Definitions • Give the conjugate acid for each of the following:

  10. - + C. Strength • Strong Acid/Base • 100% ionized in water • strong electrolyte NaOH KOH KOH RbOH CsOH Ca(OH)2 Ba(OH)2 HCl HNO3 H2SO4 HBr HI HClO4

  11. - + C. Strength • Weak Acid/Base • does not ionize completely • weak electrolyte HF CH3COOH H3PO4 H2CO3 HCN NH3

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

  13. pH water equilibrium • Pure water ionizes to a small extent to produce hydrogen ions and hydroxide ions • According to LeChatlier’s principle if an acid is dissolved in water the equilibrium will shift to the left decreasing the hydroxide ion concentration. • If a base is dissolved in water this decreases the hydrogen ion concentration.

  14. A. Ionization of Water H2O(l)+ H2O(l)H3O+(aq)+ OH- (aq) Self-Ionization of Water

  15. A. Ionization of Water Kw = [H3O+][OH-] = 1.0  10-14 Ion Product Constant for Water • The ion production of water, Kw = [H3O+][OH–] • Pure water contains equal concentrations of H+ and OH– ions, so [H3O+] = [OH–] • For all aqueous solutions, the product of the hydrogen-ion concentration and the hydroxide-ion concentration equals 1.0 x 10-14

  16. A. Ionization of Water Find the hydroxide ion concentration of 3.0  10-2 M HCl. HCl → H+ + Cl- 3.0  10-2M 3.0  10-2M [H3O+][OH-] = 1.0  10-14 [3.0  10-2][OH-] = 1.0  10-14 [OH-] = 3.3  10-13 M

  17. A. Ionization of Water Find the hydronium ion concentration of 1.4  10-3 M Ca(OH)2. Ca(OH)2→ Ca2+ + 2 OH- 1.4  10-3M 2.8  10-3M [H3O+][OH-] = 1.0  10-14 [H3O+][2.8  10-3] = 1.0  10-14 [H3O+] = 3.6  10-12 M

  18. B. pH Scale pouvoir hydrogène (Fr.) “hydrogen power” 14 0 7 INCREASING BASICITY INCREASING ACIDITY NEUTRAL pH = -log[H3O+]

  19. B. pH Scale pH of Common Substances

  20. B. pH Scale pH = -log[H3O+] pOH = -log[OH-] pH + pOH = 14

  21. B. pH Scale What is the pH of 0.050 M HNO3? pH = -log[H3O+] pH = -log[0.050] pH = 1.30 Acidic or basic? Acidic

  22. B. pH Scale What is the pH of 0.050 M Ba(OH)2? [OH-] = 0.100 M pOH = -log[OH-] pOH = -log[0.100] pOH = 1.00 pH = 13.00 Acidic or basic? Basic

  23. B. pH Scale What is the molarity of HBr in a solution that has a pOH of 9.60? pH + pOH = 14 pH + 9.60 = 14 pH = 4.40 pH = -log[H3O+] 4.40 = -log[H3O+] -4.40 = log[H3O+] [H3O+] = 4.0  10-5 M HBr Acidic

More Related