Final Exam- 9,10,11,16 Flashcards
(98 cards)
Solids with highly ordered structures are said to be ___________
Crystalline
Physical properties of liquids and solids are due to _____________ _______.
These are ______ between _______
Intermolecular forces
forces
molecules
_______ _______ reflect intermolecular force strength.
_______ _______ also reflect intermolecular fore strength.
A high ___ ___ or ___ ___ indicates strong attractive forces.
Boiling Point
Melting Point
Collectively _________ forces are intermolecular forces that exist between natural molecules
van-der-waals
Van der waals forces include
______
______
______
Dispersion forces
dipole-dipole forces
hydrogen forces
For an instant, the electron cloud become distorted. In that instant a dipole i formed.
it is called an ___________ or momentary _____.
Instantaneous or momentary dipole
One instantaneous dipole can induce another instantaneous dipole in an adjacent molecule (or atom). These two ________ ____ attract each other.
Temporary dipoles
___________ is the ease with which an electron distribution can be deformed
Polarizability
Dispersion force ______ as molecular weight ______.
Increases
Increases
The _____ _____ ____ reflects the dipole-dipole forces present.
Higher boiling point
Polar molecules _______ ____ ____
Attract each other
The partially _____ end of one molecule attracts the partially _____ end of another.
Positive
Negative
Polar molecular need to be ____ ______ to form strong ____- ___ interactions
close together
dipole-dipole
If two molecules have similar mass and size, then dipole- dipole forces ______ with ______ _______.
Increase with increasing polarity.
_______ _______ is a special type of ________ _______. This is a special case of dipole-dipole interactions.
Hydrogen bonding
intermolecular attraction
H bonding require:
H Bonded to a small _______ ______.
Most important for compounds of _, _, and _.
electronegative element
F, O, & N
Bond energies of Hydrogen bonds vary from about 4kj/mol to 25kj/mol. They are much _____ than ______ ______ _____.
weaker than ordinary chemical bonds
An interesting consequence of H-bonding is that for such a low molar mass molecule (Mm = 18g/mol) water has an unusually:
a)____ ____ _____
b)____ ____ of __________
c)water is a liquid under most circumstances
makes life possible.
d)water is a _____ _____
e) The solid has a ____ density than the liquid, causing the ice to ____.
a) High surface tension
b) High heat of vaporization (makes possible evaporative cooling)
d) Is a Superior Solvent
e) Lower density, causing Ice to float.
The molecules in solids are usually more closely packed than those in liquids.
Therefore, solids are usually denser than liquids.
But a few molecules have their solids less dense than their liquids, like
Ice to water.
An ___-___ force is an interaction between an ion (e.g., Na+) and the partial change on the end of a polar molecule/dipole (e.g. water)
Ion-dipoles
H-bonding is the _____ of the intermolecular forces while Dispersion Force is the _______.
Strongest
weakest
Ion-Dipole interaction are _____ than H-bonds
Stronger
Intermolecular attractive force will generally be ______ in the substance with the ______ ______ _____.
greater
higher molecular weight
_______ is the resistance of a liquid to flow.
Viscosity
