1. Pick up the PPT notes and the practice paper off the front demo table. PAP CHEMISTRY

2. ACIDS AND BASES www.lab-initio.com PAP Chem Chapter 1: Intro to Chem

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

4. Acids are Proton (H + ion) Donors Strong acids are assumed to be 100% ionized in solution (good H + donors). Weak acids are usually less than 5% ionized in solution (poor H + donors). HCl H 2 SO 4 HNO 3 H 3 PO 4 HC2H3O2HC2H3O2 Organic acids

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

6. 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

7. Acids Have a pH less than 7

8. Acids Taste Sour  Citric acid in citrus fruit  Malic acid in sour apples  Lactic acid in sour milk and sore muscles  Butyric acid in rancid butter Organic acids are weak acids. Some are used as flavoring agents in food.

9. Acids Effect Indicators Blue litmus paper turns red in contact with an acid. Methyl orange turns red with addition of an acid

10. Acids React with Active Metals Acids react with active metals to form salts and hydrogen gas. Mg + 2HCl  MgCl 2 + H 2 (g) Zn + 2HCl  ZnCl 2 + H 2 (g) Mg + H 2 SO 4  MgSO 4 + H 2 (g)

11. Acids React with Carbonates 2HC 2 H 3 O 2 + Na 2 CO 3 2 NaC 2 H 3 O 2 + H 2 O + CO 2

12. Effects of Acid Rain on Marble (calcium carbonate) George Washington: BEFORE George Washington: AFTER

13. Acids Neutralize Bases HCl + NaOH  NaCl + H 2 O Neutralization reactions ALWAYS produce a salt and water. H 2 SO 4 + 2NaOH  Na 2 SO 4 + 2H 2 O 2HNO 3 + Mg(OH) 2  Mg(NO 3 ) 2 + 2H 2 O OH - (hydroxide) in base combines with H + in acids to form water H + + OH -  H 2 O

14. Definitions  Arrhenius - In aqueous solution… HCl + H 2 O  H 3 O + + Cl – AcidsAcids form hydronium ions (H 3 O + ) H HHHH H Cl OO – + acid

15. Definitions  Arrhenius - In aqueous solution… BasesBases form hydroxide ions (OH - ) NH 3 + H 2 O  NH 4 + + OH - H H H H H H N NO O – + H H H H base

16. 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

17. Definitions H 2 O + HNO 3  H 3 O + + NO 3 – CBCAAB

18. Definitions - can be an acid or a base.  Amphoteric - can be an acid or a base. NH 3 + H 2 O  NH 4 + + OH - CACBBA

19. Definitions F - H 2 PO 4 - H2OH2O HF H 3 PO 4 H 3 O +  Give the conjugate base for each of the following: (these are acids) - an acid with more than one H +  Polyprotic - an acid with more than one H +

20. Definitions Br - HSO 4 - CO 3 2- HBr H 2 SO 4 HCO 3 -  Give the conjugate acid for each of the following: (these are bases-accept protons)

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

22. Acid/Base Definitions TypeAcidBase ArrheniusH+ producerOH- producer Bronsted- Lowry H+ donorH+ acceptor LewisElectron-pair acceptor Electron-pair donor

23. Acid Nomenclature

24.  HBr  H 2 CO 3  H 2 SO 3 2 elements, -ide 3 elements, -ate 3 elements, -ite  hydrobromic acid  carbonic acid  sulfurous acid Acid Nomenclature

25.  hydrofluoric acid  sulfuric acid  nitrous acid 2 elements 3 elements, -ic 3 elements, -ous  HF  H 2 SO 4  HNO 2 Acid Nomenclature  H + F-  H + SO 4 2-  H + NO 2 -

26. Properties of Bases  Bases are proton (hydrogen ion, H + ) acceptors  Bases have a pH greater than 7  Bases taste bitter  Bases effect indicators  Red litmus turns blue  Phenolphthalein turns purple  Solutions of bases feel slippery  Bases neutralize acids

27. Bases are Proton (H + ion) Acceptors  Sodium hydroxide (lye), NaOH  Potassium hydroxide, KOH  Magnesium hydroxide, Mg(OH) 2  Calcium hydroxide (lime), Ca(OH) 2

28. Bases have a pH greater than 7

29. Bases Effect Indicators Red litmus paper turns blue in contact with a base. Phenolphthalein turns bright pink in a base.

30. Bases Neutralize Acids Milk of Magnesia contains magnesium hydroxide, Mg(OH) 2, which neutralizes stomach acid, HCl. 2 HCl + Mg(OH) 2 MgCl 2 + 2 H 2 O