Acids, Bases, & Salts
What is an ACID?
• pH less than 7
What is an ACID?
• pH less than 7
• Neutralizes bases
What is an ACID?
• pH less than 7
• Neutralizes bases
+
• Forms H ions in solution
H2O H+ H2O
H2O H2O
H2O
H2O H+ +
+
H2OH H O
H
+
2
H2OH OH+ H H2O
2
What is an ACID?
• pH less than 7
• Neutralizes bases
+
• Forms H ions in solution
• Corrosive-reacts with metals
What is an ACID?
• pH less than 7
• Neutralizes bases
+
• Forms H ions in solution
• Corrosive-reacts with most
metals to form hydrogen gas
• Good conductors
of electricity
What is an ACID?
• pH less than 7
• Neutralizes bases
+
• Forms H ions in solution
• Corrosive-reacts with most metals
to form hydrogen gas
• Good conductors of electricity
• Tastes Sour
Acids Generate
Hydronium Ions
HNO3 + H2O 
H+ + H2O + NO3 
H3O+ + NO3
Weak vs. Strong Acids
• Weak Acids do not ionize completely:
Acetic, Boric, Nitrous, Phosphoric,
Sulfurous
• Strong Acids ionize completely:
Hydrochloric, Nitric; Sulfuric, Hydriodic
Common Acids
•
•
•
•
•
•
HCl- hydrochloric- stomach acid
H2SO4- sulfuric acid - car batteries
HNO3 – nitric acid - explosives
HC2H3O2- acetic acid - vinegar
H2CO3- carbonic acid – sodas
H3PO4- phosphoric acid -flavorings
What is a BASE?
• pH greater than 7
What is a BASE?
• pH greater than 7
• Feels slippery
What is a BASE?
• pH greater than 7
• Feels slippery
• Tastes Bitter
What is a BASE?
• pH greater than 7
• Feels slippery
HO
HO
OH
HOHO
H
O
• Bitter Taste
H O OH
H OOH H
OOH OH
OH
H OH OOH H O
• Usually forms
OH ions in solution
2
-
2
2
2
-
-
2
2
2
2
2
-2
-
-
-
2
What is a BASE?
• pH greater than 7
• Feels slippery
• Tastes Bitter
• Usually forms
OH ions in solution
• Neutralizes acids
What is a BASE?
•
•
•
•
pH greater than 7
Feels slippery
Tastes Bitter
Usually
forms
OH ions in solution
• Neutralizes acids
• Conducts Electricity
Common Bases
•
•
•
•
NaOH- sodium hydroxide (LYE) soaps, drain cleaner
Mg (OH)2 - magnesium hydroxide - antacids
Al(OH)3 - aluminum hydroxide - antacids, deodorants
NH4OH - ammonium hydroxide - “ammonia”
pH of Common Substances
Vinegar
Gastric
Juice
HCl
Lemon
Juice
Timberlake, Chemistry 7th Edition, page 335
pH of Common Substances
Soil
Bread
Soda
Orange
Apple
Potato
Urine
Tomato
Coffee
Timberlake, Chemistry 7th Edition, page 335
Milk
pH of Common Substances
Pure
Water
Timberlake, Chemistry 7th Edition, page 335
pH of Common Substances
Drinking
Water
Blood
Detergents
Bile
Sea Water
Timberlake, Chemistry 7th Edition, page 335
pH of Common Substances
Milk of
Magnesia
Ammonia
Bleach
Timberlake, Chemistry 7th Edition, page 335
Lye
(NaOH)
pH paper
• pH paper changes
color to indicate a
specific pH value.
Buffers
• A buffer is a solution that resists changes in
pH when small amounts of acids and bases
are added.
Situations in which pH is controlled
•
•
•
•
•
“Heartburn”
Planting vegetables and flowers
Fish Tanks and Ponds
Blood
Swimming pools
Acids and Bases in Solution
• HCl + H20  H3O + + Cl(more hydronium ions, more acidic)
Acids and Bases in Solution
• HCl + H20  H3O + + Cl(more hydronium ions, more acidic)
• NaOH in water  Na+ + OH(more hydroxide ions, more basic)
Acids and Bases in Solution
• HCl + H20  H3O + + Cl(more hydronium ions, more acidic)
• NaOH in water  Na+ + OH(more hydroxide ions, more basic)
• HCl + NaOH  NaCl + HOH
Acid + Base yields type of salt and water
Neutralization Reaction
• reaction of an acid with a base to
produce salt and water.
• Example
H2SO4 + NaOH  NaHSO4 + H2O
Acid Rain
Pollution in the air (sulfur dioxide, carbon
dioxide, nitrogen dioxide) combines with
water to form various acids.
.
Rapid changes in pH can
•kill organisms in lakes and streams.
•can kill plants and
•create sinkholes
What is a SALT?
• Composed of the negative ion of an acid
and the positive ion of a base.
• One of the products of a Neutralization
Reaction
• Examples: KCl, NaCl, MgSO4, Na3PO4
Acids, Bases, and Salts
The End