Transcript What is metallic bonding?
Slide 1
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.
Slide 2
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.
Slide 3
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.
Slide 4
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.
Slide 5
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.
Slide 6
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.
Slide 2
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.
Slide 3
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.
Slide 4
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.
Slide 5
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.
Slide 6
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
What is metallic bonding?
Metallic bonds are the forces of attraction between free-floating valence
electrons and positively charged metal cations.
• In a metal, cations are packed closely together.
• The loosely held valence electrons of the metal atoms form a “sea
of electrons” that drift freely from one part of the metal to another.
• The overall charge of the metal is neutral.
1. Describe Describe the
nature of metallic bonding.
Include in your description an
explanation of why a metal
consists of cations rather than
neutral atoms.
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
How does metallic bonding
explain metallic properties?
Some common properties of metals include:
• malleability—ability to be hammered or rolled into flat sheets or
other shapes
• ductility—ability to be pulled out, or drawn, into wires
• thermal conductivity—ability to transfer thermal energy in the form
of heat
• electrical conductivity—ability to conduct an electric current
Each of these properties may be explained by applying the “sea-ofelectrons” model of metallic bonding.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Malleability When a metal is subjected to pressure, the free-floating
valence electrons shield the cations from one another. The cations
easily slide past one another, so the metal changes shape rather than
breaking apart, as an ionic crystal does.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Ductility As with malleability, pressure
also may be exerted on metals by
forcing them through the narrow
opening of a die, for example. The
metal changes shape but remains
as one piece and emerges from
the die as a wire.
As the wire is forced
through the die, the size of
the opening in the die
determines the diameter of
the wire.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Thermal conductivity Conduction is the transfer of thermal energy with
no overall transfer of matter.
Conduction occurs within a material or between materials that are
touching. Newton’s cradle is a device that helps explain conduction.
Newton’s cradle is a model for
conduction. When a ball at one end is
pulled back and released, energy is
transferred from one ball to the next, but
only the last ball at the other end moves.
In metals, conduction is fast because the mobile valence electrons are
free to move. Collisions of electrons transfer thermal energy through
the metal.
(contd.)
TEKS 7D: Describe the nature of metallic bonding and apply the theory to explain metallic properties
such as thermal and electrical conductivity, malleability, and ductility.
Electrical conductivity An electric current is a flow of charged particles.
Metals are good conductors of electric currents because the valence
electrons can flow freely in the metal. As electrons enter one end of a
piece of metal, an equal number of electrons leaves the other end.
2. Apply Theories Apply the theory of metallic bonding
to explain the metallic properties of malleability and
thermal conductivity of aluminum foil.