Polarizability

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Transcript Polarizability

Polarizability
SiYuan Wu
Kyle See
Arya Khalesi
Reshma Mathew
Jordan Howick
What is
Polarizability?
Polarizability is the ease with which charge
distribution is distorted. The greater the
polarizability, the more easily the electron
cloud can be distorted to create an
instantaneous dipole.
More polarizable molecules have larger
dispersion forces.
Dispersion Influence
The strength of a dispersion force depends
on the ease with which the charge
distribution in a molecule can be distorted.
Polarizability usually increases as the
number of electrons in an atom or molecule
increases. Therefore, the strength of
dispersion forces tends to increase with
increasing atomic or molecular size.
Polarizability
Positively charged ions usually hold onto
their electrons tightly due to an excess of
proton in the nucleus, so their polarizability
is usually quite small. Only larger positively
charged ions can be easily polarizable.
Negative ions are easily polarizable
because they have a larger electron cloud
that tends to be more polarizable. Small,
positively charged ions can easily distort
theses negative ions.
Summary
1. Polarizability defines the molecules
ability to become polarized
2. How easily the electron cloud of a
molecule is distorted (moving to one side)
to create poles (positive and negative).
3. As Polarizability increases, dispersion
forces become stronger. Thus, molecules
attract towards one another more
vigorously and they have higher
melting/boiling points which increase with
Polarizability
Animation
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