1. Acids
and
Bases 1

2. The stomach produces HCl to aid in the digestion of food.
Hydrochloric Acid, HCl
The stomach produces HCl to aid in the digestion of food. 2

3. Base Bitter taste Turns red litmus blue Slippery to the touch
Properties of acids and bases
Acids
– Sour taste
– Turns blue litmus paper red
– Reacts with some metals to produce H2
– Dissolves carbonate salts, releasing CO2
Bases
– Bitter taste
– Turns red litmus paper blue
– Slippery to the touch
Copyright © 2007 Pearson Benjamin Cummings. All rights reserved. 3

4. IONS
H +
OH -

5. Acid + Base  Salt + Water
Neutralization Reaction
Acid + Base  Salt + Water
HCl + NaOH  NaCl + HOH
salt water 5

6. Properties ACIDS BASES electrolytes electrolytes sour taste
bitter taste
turn litmus red
turn litmus blue
react with metals to form H2 gas
slippery feel
vinegar, milk, soda, apples, citrus fruits
ammonia, lye, antacid, baking soda
ChemASAP 6

7. Common Bases Name Formula Common Name
OH1-
hydroxide
ion
Name Formula Common Name
Sodium hydroxide NaOH lye or caustic soda
Potassium hydroxide KOH lye or caustic potash
Magnesium hydroxide Mg(OH)2 milk of magnesia
Calcium hydroxide Ca(OH) 2 slaked lime
Ammonia water NH3 H2O household ammonia
Bases
– Bases are ionic compounds that contain the hydroxide ion and a metal cation and have the general formula M(OH)n .
– When a base reacts with an acid, it accepts a proton (H+) and is therefore called a proton acceptor.
– Aqueous ammonia solution is also a common base.
– Replacing a hydrogen atom of NH3 with an alkyl group results in an amine (RNH2), which is also a base. Amines have pungent odors. .
NH4OH
NH OH1-
ammonium hydroxide 7

8. Acid
Sour taste
Turns blue litmus red
Reacts with some metals to produce H2
Dissolves carbonate salts, releasing CO2

9. Common Acids and Bases Strong Acids (strong electrolytes)
Strong Bases (strong electrolytes)
NaOH sodium hydroxide
KOH potassium hydroxide
Ca(OH) calcium hydroxide
HCl hydrochloric acid
HNO3 nitric acid
HClO4 perchloric acid
H2SO4 sulfuric acid
Phosphoric acid, H3PO4, is another acid commonly found in the laboratory. It is on the borderline between a strong and weak acid.
Weak Acids (weak electrolytes)
CH3COOH acetic acid
H2CO3 carbonic
Weak Base (weak electrolyte)
NH ammonia
NH3 + H2O  NH4OH
Kotz, Purcell, Chemistry & Chemical Reactivity 1991, page 145 9

10. Compounds that show a color change in an acid or base.
Indicators
Compounds that show a color change in an acid or base.
Most indicators are weak organic acids or bases that react with ions in solution. It is this chemical reaction that produces the color change.

11. Red Cabbage Indicator
Copyright © 2007 Pearson Benjamin Cummings. All rights reserved. 11

12. pH of Common Substance 14 1 x 10-14 1 x 10-0 0 13 1 x 10-13 1 x 10-1 1
pH [H1+] [OH1-] pOH
14 1 x x
13 1 x x
12 1 x x
11 1 x x
10 1 x x
9 1 x x
8 1 x x
6 1 x x
5 1 x x
4 1 x x
3 1 x x
2 1 x x
1 1 x x
0 1 x x
NaOH, 0.1 M
Household bleach
Household ammonia
Lime water
Milk of magnesia
Borax
Baking soda
Egg white, seawater
Human blood, tears
Milk
Saliva
Rain
Black coffee
Banana
Tomatoes
Wine
Cola, vinegar
Lemon juice
Gastric juice
More basic
7 1 x x
More acidic 12

13. ELECTROLYTES
Conduct electricity
Strong acids and bases

14. TUMMY ACHE
Ca(OH)2 or
Mg(OH)2

15. Another name for household Vinegar
HC2H3O2 Acetic Acid
Another name for household Vinegar

16. pH of Common Substances
vinegar
2.8
water (pure)
7.0
soil
5.5
gastric
juice
1.6
carbonated
beverage
3.0
drinking water
7.2
bread
5.5
1.0 M
NaOH
(lye)
14.0
orange
3.5
potato
5.8
blood
7.4
1.0 M
HCl
milk of
magnesia
10.5
apple juice
3.8
urine
6.0
detergents
bile
8.0
lemon
juice
2.2
tomato
4.2
milk
6.4
ammonia
11.0
seawater
8.5
coffee
5.0
bleach
12.0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
acidic
neutral
basic
[H+] = [OH-]
Timberlake, Chemistry 7th Edition, page 335 16

17. ACIDS ex. HNO3 + H2O  H3O+ + NO3-
a) Remember that H+ reacts with H2O to produce H3O+
ex. HNO3 + H2O  H3O+ + NO3-
b) strong acids – one that completely ionizes in aqueous solution
ex. HCl and HNO3
c) weak acids –are weak electrolytes (ionize only little)
ex. HC2H3O2

18. BASES
b) strong bases – strong electrolytes; completely dissociates
ex. NaOH, KOH
c) weak bases – not very soluble in water so they don’t give off many OH- ions
ex. Mg(OH)2 and NH3 (ammonia)
NH3 + H2O  NH4+ + OH-

19. pH Paper pH pH