Chapter 6
Chemical Bonds
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Ionic Bonds Sec. 6.1
 When
elements react they tend to
transfer electrons to become stable
 Ex. Na and Cl
 When ions form the charge changes
from neutral because of a change in
the number of protons or electrons.
 Ex. Na+ and Cl-
1
2
Lose e-
3
4
5
6
Gain/ Gain eLose e-
7
Anion
Negative
charge
Have the ending –ide
Ex. Cl becomes
chloride
Cation
Positive
charge
The name is the same
as the element
+
Ex. Na is sodium
Ionic Compounds
Shows
the ratio of the atoms
in the compound
Ex. NaCl
Ex. MgCl2 (2 Cl atoms
needed)
Properties of Ionic Compounds
Strong
attraction of ions
High melting point
Not malleable
Ionic Compounds
The
name of the compound
must distinguish it from other
compounds of the same
elements
The formula describes the ratio
of the elements that make up
the compound
Naming Binary Compounds
They
follow a predictable
pattern of the cation followed
by the anion
Remember: the anion will end
in –ide
Ex. Figure 16 Common Anions
Practice with compounds
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Write the chemical formulas for the following
compounds using their valence electrons to
assist you…
Li and N
K and P H and F
Al and P
C and S Al and Br
C and Sn B and N Rb and Se
Answers
Li3N
K3 P
HF
Al3P3(AlP)
C2S4(CS2)
AlBr3
C4Sn4 (CSn)
B3N3 (BN)
Rb2Se
Naming the compounds from
previous slide
Li and N
K and P H and F
 Al and P
C and S Al and Br
 C and Sn Ba and C Rb and Se
 Lithium nitride Potassium phosphide
 Hydrogen fluoride Aluminum phosphide
 Carbon sulfide Carbon Tinide
 Aluminum Bromide Boron Nitride
 Rubidium selenide

Multiple Ions
 The
transition metals form more
than one type of ion
 Ex. Cu (I) with a 1+ charge and
Cu (II) with a 2+ charge
 The other elements have
positive charges that are equal
to their group number
Polyatomic Ions
Many
ions
Positive or negatively
charged
Figure 19
Writing Formulas for Ionic Compounds
 Determine
the ratio of elements
needed in the compound by
using the charges given.
 Ex. Na has a 1+ charge and S
has a 2- charge = Na2S
 Practice Page 174
Covalent Bonding 6.2
 Sharing
electrons (Co) means to
share
 Ex. Hydrogen
 Single bond between the elements
H-H
 H2 describes a molecule of Hydrogen
 Many nonmetals exist as diatomic
molecules
 Ex. Cl2
Multiple Covalent Bonding
Sharing
multiple
pairs of electrons
Ex. N2 has a triple
bond Page 167
Polar or Nonpolar Molecule?
 If
it has only two atoms, it is polar
 If there are more than two atoms, the
type of atoms and the shape
determine whether the molecule is
polar or nonpolar
 H2O is polar because it has a bent
shape
 Polar attractions are greater than
nonpolar
Naming Molecular Compounds
6.3
 The
most metallic element appears
first in the name
 The name of the second will end in –
ide
 Ex. N2O4 – dinitrogen tetraoxide
 NO2 – nitrogen dioxide
 Prefixes for naming compounds is
figure 20
Metallic Bonds 6.4
Metals
become cations with a
pool of shared electrons
surrounding it
The attraction between the
cation and the surrounding
electrons is the metallic bond
Properties of Metal
The
ability to conduct and
malleability are two properties
of metal that are explained by
the structure of the electrons
around the metal
Figure 22 - malleability
Alloys
 Mixture
of metals
 Copper – when mixed with tin
will produce bronze, and when
mixed with zinc will produce
brass
 Steel – a mixture of iron and
small amounts of carbon