Liquids, Solids, and Intermolecular Forces Flashcards
keeps shape when placed in a container
fixed
takes the shape of the container
Indefinite
what is not normal about water?
the density of ice is larger than liquid water
is the ability to move from one position in space to another
Translational freedom
is the ability to reorient the particles direction in space
rotational freedom
is the ability to oscillate about a particular point in space
Vibrational freedom
What state a material is in depends largely
on two major factors
1.the amount of kinetic energy the particles
possess
2.the strength of attraction between the particles
When the attractive forces are strong enough
so the kinetic energy cannot overcome it at
all, the material will be a
solid
When the attractive forces are strong enough
so the kinetic energy can only partially
overcome them, the material will be a
liquid
Intermolecular attractions are due to
attractive forces between what?
opposite charges
the larger the charge the what the attraction?
larger
the longer the distance the what the attraction
weaker
the higher the normal boiling pt the what the attraction?
stronger
Temporary polarity in the molecules due to
unequal electron distribution leads to
attractions called
dispersion forces or London forces (LIMF)
Permanent polarity in the molecules due to
their structure leads to attractive forces called
dipole–dipole attractions
An especially strong dipole–dipole attraction
results when H is attached to an extremely
electronegative atom. These are called
hydrogen bonds
what results in a temporary dipole?
Fluctuations in the electron distribution in atoms
and molecules
region with excess electron density has
partial negative charge
region with depleted electron density has
partial positive charge
The attractive forces caused by these temporary
dipoles are called
London forces
the magnitude of the dipole depends on what?
Polarizability of the electrons
and
Shape of the molecule
what force is more significant in non-polar
London Forces
what force is more significant in polar
Dipole-Dipole
what force does a hydrogen carbon molecule use?
London (nonpolar)
what does an n in front of a molecule indicate
the structure is flat
what does an iso in front of a molecule indicate
branched
what are some indicators that a molecule is polar?
- only one lone pair
- OH group
- C triple bonded to N group
- C double bonded to O group
- C double bonded to O and single bonded to OH group
- X (any halogen)
Polar molecules have a permanent dipole
dipole-dipole attractions
attractions between hydrogen connected to f, c or o to lone pair of another molecule
hydrogen bonds
has the strongest IMF
H-bonds