Chapter 20
Acids and Bases
Section 20.1
Describing Acids and Bases
 OBJECTIVES:
 Name an acid or base, when given the
formula.
Acids
Bases
Properties of acids
 Taste sour
 Conduct electricity.
 Some are strong, other are weak electrolytes
 React with metals to form hydrogen gas.
 React with bases to form water and an ionic
compound (salt).
 Turns blue litmus paper red/pink.
Properties of bases
 React with acids to form water and an ionic
compound (salt).
 Taste bitter.
 Feel slippery (don’t try this either).
 Can be strong or weak electrolytes.
 Turns red litmus paper blue
Electrolytes
Types of Acids
All have an H
 Binary Acids (Contains an H+ and an
element)
 Ex. HCl, HF, HI, H2S
 Tertiary Acids (Contains an H+ and a
polyatomic acid)
 Ex. H3(PO4), H2(SO4)
Naming Binary Acids
 1. Use prefix hydro
 2. Use root of negative element and use
suffix –ic
 3. Add acid
Example:
HCl
hydrochloric acid
H2 S
hydrosulfuric acid
Writing Formulas for Binary Acids
 1. Write the symbol H+
 2. Write the symbol for the other element with
charge.
 3. Criss-cross the charges to determine the
subscripts.
Example:
Hydrofluoric acid
Hydronitric acid
HF
H3N
Naming Tertiary Acids
1. Use the root of negative element
2. If the polyatomic ion ends with “ate”
change the ending to “ic” and add the word
acid.
***Remember, you ate something
“ICKYYY!!!:
3. If the polyatomic ion ends with “ite” change
the ending to “ous” and add the word acid.
Writing Formulas for Tertiary Acids
 Write the symbol H+
 2. Write the symbol for the other polyatomic ion with
charge.
 3. Criss-cross the charges to determine the subscripts.
Example:
Sulfuric Acid
Nitrous acid
H2(SO4)
H(NO2)
Naming Bases (Have an OH)
 1. Name the metal (If it is a transitional metal,
indicate the charge in parenthesis by uncrossing
the subscript)
 2. Name hydroxide
Example:
Mg(OH)2
Cu(OH)2
Magnesium Hydroxide
Copper (II) Hydroxide
Writing Formulas for Bases
 1. Write the symbol for the metal with charge.
 2. Write the symbol for hydroxide (OH-)
 3. Criss-Cross the charges.
Examples:
Tin (IV) Hydroxide
Sodium Hydroxide
Sn(OH)4
Na(OH)