Key Terms Chapter 8

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Key Terms Chapter 8

• Mia Carlos
• Period 1
• o1.o5.o4

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Lattice Energy
Definitionthe energy change occurring when
separated gaseous ions are packed together to
form an ionic solid.
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Single Bond
Definitiona bond in which one pair of electrons
is shared by two atoms.
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Double Bond
Definitiona bond in which two pairs of electrons
is shared by two atoms.
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Triple Bond
Definitiona bond in which three pairs of
electrons is shared by two atoms.
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Localized Electron (LE) model
Definition a model which assumes that a molecule
is composed of atoms that are bound together by
sharing pairs of electrons using the atomic
orbitals of the bound atoms.
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Lone Pair
Definition an electron pair that is localized on
a given atom an electron pair not involved in
bonding.
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Bonding Pair
Definition an electron pair found in the space
between two atoms.
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Lewis Structure
Definition a diagram of a molecule showing how
the valence electrons are arranged among the
atoms in the molecule.
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Duet Rule
Definition 2 e- He - elements - H, Li, Be, B
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Octet Rule
Definitionthe observation that atoms of
nonmetals tend to form the most stable molecules
when they are surrounded by eight electrons (to
fill their valence orbitals.)
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Resonance
Definition a condition occurring when more than
one valid Lewis structure can be written for a
particular molecule. The actual electronic
structure is not represented by any one of the
Lewis structures but by the average of all of
them.
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Resonance structure
Definitiona charge distribution close to that of
the canonical form
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Formal Charge
Definition the charge assigned of an atom in a
molecule or poly atomic ion derived from a
specific set of rules
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Molecular Structure
Definition the three-dimensional arrangement of
atoms in a molecule.

This one is Carbon-60.
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Valence Shell electron pair repulsion
DefinitionThis theory explains the shape of
molecules based on the idea that electron pairs
repel each other so that the electrons involved
in bonds try to get as far apart as possible.
For example, CO2 has two oxygen atoms double
bonded to the central carbon. The two pairs of
electrons involved in the bond all have the same
charge (negative) and so try to move as far apart
as possible, making it a linear molecule. It
would be wrong to draw the bonds closer together
than they would have to be.
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VSEPR Model
Definition a model whose main postulate is that
the structure around a given atom in a molecule
is determined principally by minimizing
electron-pair repulsions.
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Linear Structure
Definition each electron pair is shared with all
three of the atoms. (the carbon atom is shared
with each oxygen atom) with a 180 degree bond
angle
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Trigonal planar structure
Definitioneach of the electron pairs is shared
with all three atoms of Boron.
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Tetrahedral structure
Definition an arrangement of atoms that has
angles of 109.5 degrees.
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Trigonal pyramid
Definition an arrangement where one side is
different from the other three.
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Trigonal Bipyramid
Definitionarrangement of atoms that produces
minimum repulsion.
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Octahedral structure
Definitionan arrangement of six pairs of
electrons that form 90 degrees
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Square planar structure
Definition the outcome of a structure of lone
pairs at 180 degrees.