1. Acids and Bases
Thursday, March 3

2. (and other reactive metals)
Acids Versus Bases
Acid
Base (Alkali)
Conductivity
Litmus Paper
Phenolphthalein pH
Magnesium
(and other reactive metals)
Good conductor
Good conductor
Blue litmus red
Red litmus blue
Turns clear
Turns pink
< 7
> 7
Reacts to form hydrogen gas + salt
No reaction

3. Acids Versus Bases Acid Base (Alkali) Feel Taste Formula
Wet (no characteristic feel)
Slippery
Sour
Bitter
Usually begins with hydrogen
HCl –hydrochloric acid
H2SO4 – sulfuric acid
CH3COOH – acetic acid
Most bases contain the hydroxide ion (OH-)
NaOH – sodium hydroxide
NH3 – ammonia
CO32- - carbonate
HCO31- - bicarbonate

4. Acids Versus Bases Acid Base (Alkali) Def’n HCl(aq)  H+(aq) + Cl-(aq)
Acids are substances that DONATE H+ ions in aqueous solution.
Eg.
HCl(aq)  H+(aq) + Cl-(aq)
Bases are substances that give DONATE OH- ions in aqueous solution.
NaOH(aq)  Na+(aq)+ OH-(aq)

5. The pH scale is logarithmic which means:
a pH of 1
is ten times more acidic than
a pH of 2.

6. The pH Scale Acid Neutral Base # of H+ ions pH Many Moderate Few
Low pH
(from 1 to < 7 )
High pH
( > 7) 7
The higher the pH, the stronger the base
The lower the pH, the stronger the acid

7. Acid + Base  Salt + Water
6. Neutralization
What?
Acid and a base mix to form a salt and water
Acid + Base  Salt + Water
produces
H+ ions
produces
OH- ions
Lots of
types
General Formula:
HxA B(OH)y  AB H2O

8. Homework Read pp. 293-295 Read pp. 296-299 P. 295 (Q # 2, 3, 4)

9. Neutralization Examples:
hydrochloric acid + sodium hydroxide
 sodium chloride + water
HCl + NaOH  NaCl + H2O
nitric acid (pg 198) + calcium hydroxide
 calcium nitrate + water
2HNO3 + Ca(OH)2  Ca(NO3)2 + 2H2O