Chemical Bonding and
Compounds
Formula Writing and
Naming Compounds
Chemical bond
Molecules: two atoms joined together with a chemical bond;
can be the same or different types of atoms
Compounds: two or more different elements joined together
chemically
Atoms form compounds and molecules to become stable
and fill their outer shell
Chemical Formula
Tells what elements and the number of atoms of that
element that are in a compound or molecule.
2 H2O
coefficient the number of
units of each
substance
SO4-2
subscript - the
number of atoms of
a particular element
that are in a
molecule
superscript oxidation
number or the
number of
electrons
gained or lost
Ionic vs Covalent Bonding Foldable
List three examples of molecules or compounds of each
type of bond.
Place the following phrases in the appropriate section of the
foldable.
Transfer of electrons creates oppositely charged ions
Electrons are shared between atoms
Between 2 nonmetals
Between a metal and a nonmetal
Chemical Bond
Force that holds two atoms together in molecules and
compounds
Two Types
Ionic - attraction formed when atoms transfer electrons to make oppositely
charged ions. Between a metal and nonmetal (“I HOP IT is IONIC”)
Covalent - bond formed when atoms share electrons. Between a nonmetal
and nonmetal
Complete the following chart using the word bank below:
Force
Atoms
Chemical Bonds
Shared
More Stable
Nonmetal and Metal
Covalent
2 Nonmetals
to make
them
Lost or Gained
include
two kinds
are a
that hold
together
Ionic
in which
electrons are
where attraction is
between
in which
electrons are
where attraction is
between
Writing Formulas
Binary Compounds - compound composed of two elements
Oxidation numbers - the number of electrons an atom will gain or lose to become
an ion. (The number above the group number of the periodic table).
Writing Formulas
1. Write the symbol of the element with the positive oxidation
number.
2. Write the symbol of the element with the negative oxidation
number.
3.Use the criss-cross method with the charge (without the
sign) of one ion becoming the subscript of the other ion.
Compounds formed
Al+3will have
O-2a net charge of zero.
Al2O3
Practice
Write the Formulas between the following two elements
1. Lithium and Bromine
2. Barium and Fluorine
3. Potassium and Iodine
4. Sodium and Nitrogen
5. Magnesium and Fluorine
Naming Ionic Compounds
1. Name the metal first.
2. Write the root of the nonmetal (chlorine is chlor-, oxygen
is ox-, bromine is brom-)
3. Slap -ide on the backside of the root of the nonmetal.
(phosphide, sulfide, fluoride)
Ex: NaCl - sodium chloride, MgO - magnesium oxide
Naming Covalent Compounds
1. Use prefixes to indicate number of
atoms. The prefix mono- (one) is never
used for the first element.
2. Slap -ide on the backside of the 2nd
nonmetal.
Ex: CO2 - carbon dioxide and
P2S5 - diphosphorus pentasulfide
Name the following binary compounds. Be
sure to tell if each is ionic or covalent first,
then name accordingly.
1. CaBr2
2. N2F4
3. CS2
4. CO
5. H2O
6. AgCl
Polyatomic Ions - charged molecule
composed of two or more atoms that act
as a single unit.
Transition Metals
When writing and naming transition metals you must use a
roman numeral, which indicates the oxidation number for
that transition metal.