Dipole-Dipole

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Dipole-Dipole

• An intermolecular force that exists between polar
  molecules.

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Definition in English

• Dipole-Dipole force is a type of intermolecular
  force/bonding.
• Its the attraction between opposite charges
  (negative and positive) of molecules that are
  close together.

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What Molecules it Applies to

• Dipole Dipole forces applies to any polar
  molecule
• A polar molecule is a molecule with a partial
  positive charge on one side and a partial
  negative charge on the other sides.
• (think like a magnet!)

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Conditions?

• First There needs to be at least 2 polar
  molecules close together .
• Second The two polar molecules must be facing
  opposite ends for the process of the bonding.
• Negative faces Positive, and vice-versa.

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One Step FurtherHow would you apply
dipole-dipole bonding to solubility?

• Solubility is defined as the quantity of a
  particular substance that can dissolve in a
  particular solvent. Dipole-Dipole bonding shows
  which substance can dissolve in what solvent.

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More Info!

• Permanent Dipole- The result of the covalent
  bonding between 2 different molecules.
• (Also known as dipole-dipole interactions and
  exist between polar molecules)
• All diatomic molecules (molecules composed only
  of two atoms, of either the same or different
  chemical elements) with polar bonds form
  permanent dipoles.

• The strengths of intermolecular attractions
  increase when polarity increases.
• When polar molecules bond, they are said to have
  a dipole moment.
• Strength of the force depends on the polarity of
  the molecule.

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Scenario
The two couples are two polar molecules. Girl is
positive, bonded already (permanent dipole) with
a negative boy. They come close to another
couple. Positive girl is facing negative
boywhat do you think will happen?
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Example
Dipole Dipole Force (Attraction!)

• HCl -The reaction of the dipole-dipole force
  aligns HCl as seen below.

Negative
Positive
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What Have We Learned?

• Dipole-Dipole force- a type of intermolecular
  force / bonding.
• It requires at least two polar molecules with
  opposite charges facing each other for bonding.
• A Permanent Dipole is the result of the covalent
  bonding between 2 different molecules.
• All diatomic molecules with polar bonds form
  permanent dipoles.