Concepts:
Types of Bonds Among
Liquids and Solids
By:
I Schnizzle
Overview
In this powerpoint I’ll be talking about the
types of bonds that liquids and solids can
make depending on the type of compound
they are.
There are three major types of
intermolecular forces: Dipole-dipole
Forces, London Dispersion Forces, and
Hydrogen Bonds.
Intermolecular Forces
Intermolecular Forces are attractive forces
between molecules.
Intramoecular Forces are forces that hold
atoms together within a molecule.
These two forces are very often confused
with one another since they sound similar
but just remember that inter is between will
intra is within so naturally intra will be
stronger than inter.
Intermolecular Forces:
Van der Waals Forces
There are two types of Van der Waals
Forces and these are Dipole-Dipole and
London Dispersion forces.
The difference between these two types of
forces is that Dipole-Dipole involves
neutral, polar molecules.
The forces between the positive and
negative ends of a molecule are held
together with a dipole-dipole (d-d) force.
Intermolecular Forces:
Van der Waals Forces Cont’
Since polarity is involved with d-d forces the
greater the polarity the more the d-d attraction
creating such things as higher melting and
boiling points, even though the attractions are
relatively weak within d-d forces.
Substances that experience D-D forces are
usually gases or liquids at room temperature.
London Dispersion Forces are those that involve
neutral, nonpolar molecules.
Intermolecular Forces:
Van der Waals Forces Cont’
These London Dispersion (L-D) forces are very
weak in nature and occur because of the
random shifting and motion of electrons on
atoms within a given molecule.
Since the L-D forces rely on electrons there can
be at some instances a split second of time
where a dipole moment occurs such as when
more electrons are on one side of an atom than
the other.
Also because of the reliance on electrons L-D
forces are naturally stronger when there are
more electrons on an atom.
Intermolecular Forces:
Van der Waals Forces Cont’
These L-D forces are very weak however
and so even though they might be
stronger with the more electrons there are
their melting and boiling points are still
very low.
Finally, since these points are so low these
substances that experience L-D forces are
usually gases at room temperature.
Hydrogen Bonds
Hydrogen bonds are the last major type of
Intermolecular forces and are by far the
strongest.
Like d-d forces hydrogen bonds involve the
positively charged end of one molecule to be
attracted to the negatively charged side of
another molecule.
The difference among the two forces is that the
negatively charged end of the other molecule is
one that is extremely electronegative such as
N,O, or F.
Hydrogen Bonds
The reason that they Hydrogen bonds are that
much stronger than their similar d-d bonds is
that once the H atom releases its lone electron
to the bond the nucleus is left unshielded.
This causes the bond to be very strong and
allows for substances that have hydrogen bonds
like water to have higher melting and boiling
points than other substances that have d-d
forces instead.
Conclusion
Dipole-Dipole= forces between neutral, polar
molecules. Not very strong
London Dispersion forces= forces between
neutral, nonpolar molecules. Weaker than the
Dipole-Dipole forces.
Hydrogen Bonds- forces like Dipole-Dipole
except the negatively charged end of one
molecule is very electronegative like N,O, or F.
Strong bond since nucleus is left unshielded.
And that’s all she
Wrote
Shout out to my juniors:
Canada, Dani, Tony, Mike, and James
Hi to you to Kaiye (if I spelled that right)
and of course
SANDRA OH BABY!??!?!