1. More on Acids and Bases

2. Acids
Acids are compounds that increase the concentration of hydrogen ions [H+] when they dissolve in water.
Acids solution have:
pH below 7
Taste sour
Turn litmus paper red.

3. Bases
Bases are compounds that increase the concentration of hydroxide ions [OH-] when they dissolve in water.
Bases have:
pH greater than 7
Taste bitter
Feel slippery
Turn litmus paper blue

4. pH
pH (0-14) measures the hydrogen ion concentration in water.
Each pH unit involves a tenfold change in hydrogen ion concentration.
The pH number and the [H+] are inversely related because
pH = - log [H+]

5. pH continued
An increase of 1 pH unit means that the hydrogen ion concentration has decreased 10 times.
A decrease of 1 pH unit means that the hydrogen ion concentration has increased 10 times.

6. Arrhenius Arrhenius acids form hydrogen ions in aqueous solutions
Arrhenius bases form hydroxide ions in aqueous solutions.

7. Bronsted-Lowry
Acids are proton donors
Bases are proton acceptors

8. Lewis Lewis Acids can accept a pair of electrons
Lewis Bases can donate a pair of electrons

9. Strong Acids & Bases
Both strong acids and bases dissociate completely in water, and therefore are strong electrolytes.
In a solution of a strong acid like hydrochloric acid, almost all of the HCl molecules dissociate:
HCl  H+ + Cl-
When 1 mole of HCl dissociates, it produces 2 moles of ions.

10. Weak Acids and Bases
Weak acids and bases are weak electrolytes and only partially dissociate..
In a solution of a weak acid like acetic acid, only a few of the CH3COOH molecules dissociate
CH3COOH  H+ + CH3COO-
When 1 mole of CH3COOH dissociates it produces LESS than 2 moles of ions because only some of the molecules dissociate.

11. pH of weak Acids and Bases
A 1 M solution of HCl would have a LOWER pH than a 1M solution of CH3COOH because HCl produces more moles of H+ with its greater degree of dissociation.

12. Acid Base Pop Quiz If the pH is 4 what is the pNeutral?
If the concentration of water is 30M, then what is the ABC?
If the indicator was Hydronium, what happened in the titration

13. This quiz was a JOKE!!!
Next time, BE PREPARED FOR CLASS!!!