9:26 AM M.
B
LTE
Exercise_10.3_-_Intermolecular_...
Name:
KEY
AP Chemistry
Exercise 10.3
Intermolecular Forces
Date:
Per:
Types of Solids
Intermolecular Force(s) Between Particles
1. Metallic Crystals (Metals)
Metallic bonding: Valence electrons form mobile sea of electrons which comprise the metallic bond.
Ex: Na, Cu, Fe, Mn 2. Ionic Crystals (Ionic Solids)
Ionic Bonding/Ion-dipole: Attraction of charged ions for one another. Lattice energy is a measure of ionic bond strength. Attractive force between an ion and
Ex: NaCl, MgCl2, MgO
an oppositely charged end of a permanent dipole possessed by a neutral
molecule.
3. Network Covalent Crystals
Network covalent bonding. Network solids are extremely hard compounds with very high melting and boiling points due to their endless 3-dimensional network
Ex: C(diamond), SiC(s), SiO2(quartz) 4. Molecular Crystals
of covalent bonds. Hydrogen bonding: Hydrogen bonds are weaker than covalent bonds, but stronger than (b) or (c) below. A hydrogen atom attached to one of these three
One or more of the following:
(a) Need H bonded to O, N or F:
(a)
Ex: H₂O, HF, NH3.
elements possesses a substantial partial positive charge. The positive end of each
of the bond dipoles (H atom) is capable of strongly interacting with an unshared
electron pair possessed by N, O, or F atom of an adjacent molecule.
(b) CHF3, CH,COCH, (acetone) and H₂O, HF, NHS.
(b) Dipole-dipole forces: these forces act between polar molecules. They are much
weaker than hydrogen bonding. Positive end of permanent dipole on one molecule aligns itself with negative end of permanent dipole on another molecule. Only significant in effect when molecules are close together. They usually dominate over (c) below.
(c) CH (benzene),
(c) Dispersion forces (induced dipole-induced dipole or London dispersion forces): universal force of attraction between instantaneous dipoles. These forces are the compounds from (a) and weak for small, low-molecular weight molecules, but greater for heavy, long, and/or highly polarizable molecules with increasing molecular volume. Short range attractive forces between molecules resulting from momentary mutual distortion (polarization) of electron clouds. Dispersion forces: See Section 4(c) above.
polyethylene, 12, F2, and all
(b) above.
5. Atomic Crystals Ex: He, Ne, Ar, Kr, Xe
*Note: Many of the compounds given as examples are not solids at room temperature. But if you cool them down to a low enough temperature, eventually they will become solids.
2 FIXED THIS PART
The physical properties of a substance depend on its intermolecular forces. The stronger the forces between particles,
a.
b. the higher lower the boiling point.
C.
the higher lower the melting point.
the higher Tower the vapor pressure.
the higher lower the viscosity (resistance to flow). the higher lower the surface tension (resistance to an increase in surface area).
d.
2.
What type of crystal will each of the following substances form in its solid state? Choices to consider are metallic, ionic,
covalent, or molecular crystals. (a) C₂H₂ MOLECULAR
(d) CO₂
MOLECULAR
(8) AI METALLIC
(b) Na2O IONIC
(e) N₂Os
MOLECULAR (f) NaNO, IONIC
(h) C(diamond) COVALENT
(c) SiO2
COVALENT
(1) SO₂ MOLECULAR
3. Circle all the compounds in the following list which would be expected to form intermolecular hydrogen bonds in the liquid state:
(CHOCH
(dimethyl ether)
(b) CH4 H
(c) HF (d) CH,CO,H
(e) Brz
(f) CH3OH (methanol)
H-C-O-C-H Revised: 2019-02-21
H-C-H
C-C-O-H
:Br
no N, O, F to H BOND
H-F: H
H
H
H
Chemistry
Exercise 10.3
Name:
Date:
Per