Miss Elaine Macalinao
Chemistry
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Chemical bond: a mutual electrical attraction between the
nuclei and valence electrons of different atoms that binds the
atom together
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Why form chemical bonds?
 Decrease potential energy
 Increase stability
 All atoms trying to achieve a stable octet
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When atoms bond, their valence electrons are moved around in
ways that make the atoms more stable
The way their valence electrons move around determine the
type of bond that happens
 3 major types of chemical bonds:
▪ Ionic
▪ Covalent
▪ Metallic
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Ionic bond: chemical bonding that
results from the electrical attraction
between large numbers of cations
and anions
Electrons are either gained or lost by
an atom
 In doing so, both atoms often
achieve the electron configuration
of the nearest noble gas
Occurs between metals losing
electrons to nonmetals
Very strong bond
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Ionic compound: composed
of positive and negative ions
that are combined so that
the numbers of positive and
negative charges are equal
 Most ionic compounds exist as
crystalline solids
▪ 3D network of positive and
negative ions mutually attracted
to one another
▪ Ex: rocks, minerals
IONIC
Definition
Chemical bonding that results from the electrical
attraction between large numbers of cations and
anions
Types of atoms involved
Metals & nonmetals
Method of bond formation
Transfer of electrons
Type of structure
Crystal lattice
Physical state
Solid
Melting point
High
Solubility in water
Yes
Electrical conductivity
Yes
Other properties
--
Image
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Covalent bond: chemical bonding that results from the
sharing of electron pairs between two atoms
Neither atom has an electrical charge
Forces between atoms are weak
Bonding between atoms of the same elements is completely
covalent
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Molecule: a neutral group of atoms that are held together by
covalent bonds
Molecular compound: a chemical compound whose simplest
units are molecules
Diatomic molecule: a molecule containing only two atoms
COVALENT
Definition
Chemical bonding that results from the sharing of
electron pairs between atoms
Types of atoms involved
Nonmetals
Method of bond formation
Sharing of electrons
Type of structure
Molecules
Physical state
Liquid or gas
Melting point
Low
Solubility in water
Usually not
Electrical conductivity
No
Other properties
Odorous
Image
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Metallic bonding: the chemical bonding that results from the
attraction between metal atoms and the surrounding sea of
electrons
Within metals, vacant orbitals allow the atoms’ outer energy
levels to overlap
 Result = electrons become delocalized
▪ Delocalized: not belonging to any one atom, but freely move
about the metal’s network of empty atomic orbitals
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Metallic Properties
 High electrical and heat
conductivity due to the freedom of
electrons to move in a network of
metals
 De-excitation responsible for the
shiny appearance of metal
surfaces
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Two important properties related to
characteristics of metals:
 Malleability: the ability of a substance
to be hammered or beaten into thin
sheets
 Ductility: ability of a substance to be
drawn, pulled, or extruded through a
small opening to produce a wire
Characteristics possible because metallic
bonding is the same in all directions
throughout the solid
METALLIC
Definition
Chemical bonding that results from the attraction
between metal atoms and the surrounding sea of
electrons
Types of atoms involved
Metals
Method of bond formation
Electrons are delocalized among metal atoms
Type of structure
“Sea of electrons”
Physical state
Solid
Melting point
Very high
Solubility in water
Yes
Electrical conductivity
Yes
Other properties
Malleable, ductile, lustrous
Image
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Most bonds are a blend of ionic and
covalent characteristics
Difference in electronegativity
determines the bond type
 A large difference in
electronegativity in a bond will
result in ionic bonding
 A small difference between two
atoms will results in covalent
bonding
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Non-polar covalent bond: a
covalent bond in which the
bonding electrons are shared
equally by the bonded atoms,
resulting in a balanced
distribution of electrical
charge
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Polar-covalent bond: a
covalent bond in which the
bonded atoms have an
unequal attraction for shared
electrons
Electronegativity
Difference
Bonding type
Non-polar covalent
0.0 – 0.3
Polar covalent
0.4 – 1.9
Ionic
2.0 – 3.3
How it looks like
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Chemical Bonding Video
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Choose one of the following products to demonstrate
what you have learned:
 Story – choose one type of bonding and write “A Day in the Life
of an Atom” story describing your chosen bond type. The story
should incorporate at least 5 properties from your Bonding
Chart
 Comic Strip – Create a comic strip with 3+ frame for each
bonding type. The comic should incorporate at least 3
properties from your Bonding Chart.
 Single-Frame Cartoon- Draw a single-frame cartoon for each
type of bonding. Each cartoon should incorporate at least 2 key
properties from your Bonding Chart.
 Essay – write a 5-paragraph essay comparing and contrasting
each bonding type. The essay should incorporate the major
properties from the Bonding Chart.