1. Acids and Bases

2. Recall Acids are compounds that start with hydrogen (H+)
HCl (hydrochloric acid)
H2SO4 (sulfuric acid)
Bases are compounds that end with hydroxide (OH-)
NaOH (sodium hydroxide)
Mg(OH)2 (magnesium hydroxide)

3. Properties of Acids Sour tasting Turn blue litmus paper red
Electrolytes
HBr(aq)  H+(aq) + Br-(aq)
Neutralize bases
HCl(aq) + KOH(aq)  KCl(aq) + H2O(l)
React with metals to produce H2 (g)
2HNO3(aq) + Zn(s)  H2(g) + Zn(NO3)2(aq)
React with carbonates to produce CO2
2HCl + Na2CO3(s) → 2NaCl(aq) + CO2(aq) + H2O(l)

4. Common Acids
carbonic acid
citric acid
sulfuric acid
acetic acid

5. Properties of Bases Bitter tasting Slippery feel
Turn red litmus paper blue
Electrolytes
LiOH(aq)  Li+(aq) + OH-(aq)
Neutralize acids
HCl(aq) + Mg(OH)2(s)  MgCl2(aq) + H2O(l)

6. Common Bases sodium hydroxide magnesium hydroxide sodium bicarbonate
ammonia

7. Arrhenius’ Theory
An acid is a substance that dissociates in water to produce one or more hydrogen ions (H+)
A base is a substance that dissociates in water to form one or more hydroxide ions (OH-)

8. Percent Ionization
Percentage of molecules that form ions in solution

11. Strong Acids Ionize completely (>99%) in water [H+] = [Acid]
High electrical conductivity
Very low pH
The corrosive property of acids is attributed to the hydrogen ion

12. Strong Bases Ionic hydroxides (NaOH, KOH, Ba(OH)2)
Ionize completely (>99%) in water
[OH-] = [Base]
High electrical conductivity
Very high pH

13. Weak Acids Percent ionization <50% [H+] < [Acid]
Low electrical conductivity
pH < 7
Dilute weak acids are safer to handle and even to eat or drink
Acetic acid, citric acid, carbonic acid

14. Weak Bases Percent ionization <50% Low electrical conductivity
pH > 7
Ammonia (NH3), sodium bicarbonate NaHCO3

15. Practice!
P. 379 # 2-5,11
P. 392 #1-4