Writing Formulas!
All compounds and
molecules are neutral.
Ions have charges.
Bonding - a chemical attachment
that forms a new substance.
This new substance has new
chemical and physical properties
Example:
Sodium is an explosive metal.
Chlorine is a toxic gas.
Sodium chloride is salt.
Metals



Tend to lose eConductors
Malleable and ductile
Nonmetals
Tend to gain e Non-conductors
 Brittle

Most common charges
+3 ±4 -3 -2 -1 0
+1+2
variable charges
(always positive)
+1 +2

Remember…
Opposites
attract
I. Bonds
Ionic Bond- an exchange of electrons between
a metal and a nonmetal.
This creates oppositely charge ions that are
attracted to each other.
-Gaining e- forms an anion (- ion)
-Onions make you cry
-Anions are negative
-Losing
-Cats
e- forms a cation (+ ion)
have paws
-Cations are pawsitive
I. Bonds
B. Covalent Bonds
- Formed by sharing electrons
- Between two nonmetal atoms
C. Metallic Bonds
- Formed by a sea of electrons
passing over the metal atoms
- flexible connection, does not
form a fixed molecule
II. Compounds
A. Ionic Compounds
- They only have two
elements
- the total amount of
positive charge must
equal the total
amount of negative
charge
Compounds
MUST be
neutral
II. Compounds
A. Ionic Compounds
- subscripts are used to show
how many of each element
is needed to balance the
overall charge
II. Compounds
A. Ionic Compounds
- the metal's name does not
change
- the nonmetal retains the root of
its name and adds the suffix ide
Sodium and Chlorine
-
+
11+
11+ and 10- = 1+
Na+
17+
17+ and 18- = 1-
NaCl sodium chloride
Cl-
Magnesium and Oxygen
2+
2-
12+
8+
12+ and 10- = 2+
8+ and 10- = 2-
Mg2+
O2MgO magnesium oxide
Magnesium and Chlorine
-
-
2+
17+
12+
17+
17+ and 18- = 1-
12+ and 10- = 2+
17+ and 18- = 1-
Cl-
Mg2+
Cl-
MgCl2 magnesium chloride
Ionic Nomenclature
What is the formula for
sodium chloride
What are the symbols and charges?
Na
+1 and
-1
Cl
How many of each atom is needed
to make the compound neutral?
NaCl
Ionic Nomenclature
What is the formula for
sodium oxide
What are the symbols and charges?
Na
+1 and
-2
O
How many of each atom is needed
to make the compound neutral?
Na2O
Ionic Nomenclature
What is the formula for
aluminum chloride
What are the symbols and charges?
Al
+3 and
-1
Cl
How many of each atom is needed
to make the compound neutral?
AlCl3
Ionic Nomenclature
What is the formula for
aluminum oxide
What are the symbols and charges?
Al
+3 and
O
-2
How many of each atom is needed
to make the compound neutral?
Al2O3
II. Compounds
A. Ionic Compounds
- the formula of an ionic compound
must be in the lowest whole
number ratio of the two elements
to form a neutral compound
(empirical formula)
Ionic Nomenclature
What is the formula for
magnesium oxide
What are the symbols and charges?
Mg
+2 and
O
-2
How many of each atom is needed
to make the compound neutral?
MgO
II. Compounds
A. Ionic Compounds
- metals with variable charges
must include the charge in the
name using Roman numerals
Ionic Nomenclature
What is the formula for
lead (II) oxide
What are the symbols and charges?
Pb
+2 and
O
-2
How many of each atom is needed
to make the compound neutral?
PbO
Ionic Nomenclature
What is the formula for
manganese (IV) oxide
What are the symbols and charges?
Mn
+4 and
O
-2
How many of each atom is needed
to make the compound neutral?
MnO2
Ionic Nomenclature
What is the formula for
copper (II) nitride
What are the symbols and charges?
Cu
+2 and
N
-3
How many of each atom is needed
to make the compound neutral?
Cu3N2
II. Compounds
A. Ionic Compounds
2. Polyatomic ion Compounds
Polyatomic ions- a group of
covalently bonded atoms
with an overall charge that
react as a group
Ionic Nomenclature
What is the formula for
copper (II) sulfate
What are the symbols and charges?
+2
Cu and
SO4
-2
How many of each atom is needed
to make the compound neutral?
Cu SO4
Ionic Nomenclature
What is the formula for
sodium sulfate
What are the symbols and charges?
+1
Na and
SO4
-2
How many of each atom is needed
to make the compound neutral?
Na2 SO4
II. Compounds
A. Ionic Compounds
2. Polyatomic ion Compounds
If more than one polyatomic
ion is needed to make a
neutral compound, you
must use parenthesis to
group the ion.
Ionic Nomenclature
What is the formula for
barium hydroxide
What are the symbols and charges?
+2
Ba and
OH
-1
How many of each atom is needed
to make the compound neutral?
Ba(OH)2
Ionic Nomenclature
What is the formula for
aluminum sulfate
What are the symbols and charges?
+3
Al and
SO4
-2
How many of each atom is needed
to make the compound neutral?
Al2 (SO4)3
Nonmetals



Tend to gain eNonconductor
Brittle
II. Compounds
B. Covalent (Molecular) Compounds
Nonmetals want to gain
electrons. When two
nonmetals are together,
they share the electrons.
Hydrogen and Hydrogen
H2
H
H
Nitrogen and Hydrogen (Ammonia)
NH3
H
H
N
H
Hydrogen and Oxygen
H2O
O
H
H
II. Compounds
Naming covalent compounds
- Because covalent compounds may
form different compounds
between two nonmetals with
different ratios, the subscripts are
denoted in the name by a prefix.
Covalent Nomenclature
1
2
3
4
5
mono
di
tri
tetra
pent
6 hex
7 hept
8 oct
9 non
10 dec
II. Compounds
Naming covalent compounds
- The element on the left will go first in the name.
- The element on the right will go last
in the name. The root remains the same, but
the suffix –ide is added.
- The prefix in front of each element give the
number of atoms (subscript written behind.)
Covalent Nomenclature
What is the formula for
carbon monoxide
1 carbon 1 oxide
CO
Covalent Nomenclature
What is the formula for
carbon dioxide
1 carbon 2 oxide
CO2
Covalent Nomenclature
What is the formula for
diphosphorus pentoxide
2 phosphorus 5 oxide
P2O5
Is it covalent or ionic?
Covalent
Ionic
- Look for prefixes
(except dichromate)
- metal & nonmetal or
metal & polyatomic
- 2 nonmetals
- write the symbol and charge
- prefixes become
subscripts
- balance charges to form a
neutral compound
(crisscross)
- Remember these
are the easy ones.
No charges!
No crisscross!
- check to make sure you have
the lowest whole number ratio!
Write the formulas for these
lithium permanganate
 tetraiodide monoxide
 tin (II) oxide
 tin (IV) oxide
 diphosphorus pentoxide
 aluminum dichromate
 tetrasulfur hexaphosphide

Write the names of the following:
 KCl
 Cl2O7
 CuSO3
 CO2
 CrN
 NaNO3
 Sb2S3
Write the formulas for these
nitrogen trioxide
 magnesium cyanide
 copper (II) hydroxide
 carbon tetrafluoride
 iron (III) bicarbonate
 manganese (IV) chlorite
 iron (III) carbonate

Write the names of the following:
 BaCl2
 CaSO4
 (NH4)2O
 LiCN
 Fe(OH)3
 Na3N
 NiPO4
Write the names of the following:
 N2O
 NO2
 PbO
 PbO2
 Na2S
 CBr4
 (NH4)2CO3
II. Compounds
C. Acids - (Special Ionic Compounds)
3. Acids- ionic compounds that
start with H+1 plus an anion
The anion changes its suffix:
-ate converts to -ic acid
-ite converts to -ous acid
-ide converts to hydro--ic acid
II. Compounds
C. Acids - (Special Ionic Compounds)
3. Acids- ionic compounds that
start with H+1 plus an anion
You –ate something and
it made you s–ick,
and you mite give it to -ous.
Acidic Nomenclature
What is the formula for
hydrochloric acid
What are the symbols and charges?
+1
H and
Cl
-1
How many of each atom is needed
to make the compound neutral?
HCl
Acidic Nomenclature
What is the formula for
sulfurous acid
What are the symbols and charges?
+1
H and
SO3
-2
How many of each atom is needed
to make the compound neutral?
H2SO3
Acidic Nomenclature
What is the formula for
sulfuric acid
What are the symbols and charges?
+1
H and
SO4
-2
How many of each atom is needed
to make the compound neutral?
H2SO4
Acidic Nomenclature
What is the formula for
chromic acid
What are the symbols and charges?
+1
H and
CrO4
-2
How many of each atom is needed
to make the compound neutral?
H2CrO4
Write the names of the following:
 HBr
 H2SO4
 H3PO4
 HNO2
 HC2H3O2
 H2CO3
Write the formulas for these
 chloric
acid
 sulfurous acid
 chromic acid
 hydrophosphoric acid
 carbonic acid
 hydroiodic acid