1. Objective: To differentiate between acids and bases Do Now: List some everyday acids and bases

2. Properties of an Acid Hydrogen containing compounds that form H + when ionized (HCl, HF, HNO 3, H 2 CO 3 ) In aqueous solution (water as solvent), they form hydronium ions (H 3 O + ) Give food a tart or sour taste Reacts with metals to form hydrogen gas (acid in aqueous solution)

3. Acids you are responsible for Sulfuric acid (H 2 SO 4 )– strong Hydrochloric acid (HCl) –strong Nitric Acid (HNO 3 ) – strong Phosphoric Acid (H 3 PO 4 ) – strong Citric acid (H 3 C 6 H 5 O 7 )– weak Acetic Acid (CH 3 CO 2 H) – weak Carbonic Acid (H 2 CO 3 )- weak Boric Acid (H 3 BO 3 ) - weak

4. Properties of Bases Yields hydroxide (OH - ) ion when ionized (NaOH, KOH, NH 3 ) Has a bitter taste (quite dangerous to test) Feel slippery (soap)

5. Bases you are Responsible For Ammonia (NH 3 )- weak Sodium Bicarbonate (Na 2 CO 3 )- weak Metal Hydroxide (XOH) – strong – Sodium Hydroxide – Potassium Hydroxide – Calcium Hydroxide (weaker of the strong) – Magnesium Hydroxide (weaker of the strong)

6. Similarities of Acids/Bases Both are electrolytes (conducts electric currents) Both reacts with pH indicators Both react with water (solubility)

7. Acids/Bases reactions When acid reacts with water HCl + H 2 O H 3 O + + Cl - When base reacts with water NH 3 + H 2 ONH 4 + + OH -

8. Acid Base Reaction (cont) When acid reacts with base HCl + NaOH NaCl + H 2 O It neutralizes the acid and base by producing salt and water

9. pH Use to determine the strength of acid or base pH = 7 (neutral) pH > 7 (basic) pH <7 (acidic)

10. Calculate pH pH = -log ([H + ]) pH = -log (1.0 x 10 -6 ) = 6 pH = -log (1.0 x 10 -9 ) = 9

11. Calculate the pH and determine if it is basic, acidic, or neutral [H + ] = 0.045M [H + ] = 1.2 x 10 -3 M [H + ] = 0.00015M

12. Measuring pH Different pH indicators for different pH ranges

13. Strong acids/bases v. weak acids/bases Strong acids/bases: completely ionizes in aqueous solution – Sodium hydroxide, potassium hydroxide, hydrochloric acid, hydro bromic acid, nitric acid, citric acid Weak acids/bases: ionizes partially in aqueous solution – Ammonia, acetic acid, baking soda, carbonic acid

15. Acid/Base Dissociation Constant (K a /K b ) Ratio of concentration of dissociated form versus non dissociated form -Strong acids/bases has large Ka/Kb -Weak acids/bases has small Ka/Kb

16. Ka and Kb values you need to know Sulfuric Acid, Hydrochloric Acid, Nitric Acid Large Ka Carbonic Acid – Ka= 4.2 x 10 -7 Phosphoric Acid – Ka= 7.5 x 10 -3

17. Ka and Kb values you need to know Acetic Acid Ka= 1.8 x 10-5 Boric Acid – Ka= 5.4 x 10 -10 Citric Acid – Ka= 3.2 x 10-7 Ammonia Kb = 1.8 x 10 -5 Carbonates Kb = 2.1 x 10 -4 Hydroxides Kb = 55.5