Notes

Chap 12 Test Review
1. Know the 3 states of matter (not including plasma) and how each state of matter can be
explained in terms of the kinetic energy of the particles at each state
2. Understand that the kinetic-molecular model is just that-- b/c it has certain assumptions
that are not always met. However, it is useful for explaining how states of matter
behave and for understanding the 6 different types of phase change (going from one
state to another).
3. Know the relationship between kinetic energy (KE) and temperature; understand what
KE means in terms of how much movement exists for the particles in each state of
matter
4. Know that the pressure that a gas exerts on its container is the outward push and that in
a regular laboratory there is always the pressure exerted by the gases of earth’s
atmosphere on everything. (The study of the behavior of gases under pressure is
pneumatics.)
5. Know the experiment that Torricelli did to measure air pressure.
6. Recognize the units used to express air pressure: pascal, torr, psi, mm Hg, atm and
millibar.
7. Know Dalton’s law of partial pressure.
8. Know the intermolecular forces: dispersion forces exist between/among all particles and
are weak when particles are small but are stronger as particle size increases;
dipole-dipole exist between/among polar covalent molecules all of the time, being
stronger than dispersion forces when the polar covalent molecules are small and highly
polar but not as strong a dispersion forces when polar covalent molecules increase in
size or are weakly polar. Hydrogen bonding is a special case of dipole-dipole force that
exists when hydrogen atoms are bonded to highly electronegative atoms.
9. Know that liquids are only slightly compressible compared to gases; the studies of these
behaviors in liquids includes hydraulics, hydrostatics and hydrodynamics.
10. Know the properties of liquids and what particle behavior contributes to them: fluidity,
viscosity and its relation to temperature, the effects of adhesion and
cohesion—including surface tension and capillary action.
11. Know the amorphous and crystalline natures of solids.
12. Know the 5 categories of crystalline solids: atomic, molecular, covalent networks, ionic
and metallic. (go back to chap 3 if you need more review)
13. Know the phase changes that require an input of energy; melting, vaporizing, boiling,
sublimation; the phase changes that release energy: freezing, condensing, deposition.
14. Know how to read a phase diagram and where to find the triple point and what it
means: temperature vs pressure graph and the point at which all 6 phases can exist.
15. Be able to respond to the article on Chocolate Chemistry, p. 431.
Chapter 13: Gases: What you need to know
1. Kinetic-molecular theory of gases: see text for all of its points
2. Know that air pressure or atmospheric pressure or gas pressure can be expressed in
different units: Table 1, p. 407.
3. Know that a volume of a fixed amount of gas is inversely proportional to its pressure
when the temperature is constant: V = 1 P1 V 2 P2
4. Know that the volume of a fixed amount of gas is directly proportional to its Kelvin
temperature when the pressure is constant: = T1
V 1
T2
V 2
5. Know that the pressure of a fixed amount of gas is directly proportional to its Kelvin
temperature when the volume is constant: = T1
P1
T2
P2
6. Know that the combined gas laws are a single statement:
, when the # of moles of the gas is constant (unchanging/fixed amount) T1
P1 V 1 = T2
P2V 2
and T is in Kelvins.
7. Avogadro’s principle: equal volumes of different gases at the same T and P contain equal
numbers of particles (atoms, molecules, etc). Molar volume derives from this principle:
when the number of particles is 1 mole and T=0.0*C and P= 1 atm (STP), then the
volume=22.4 L. (Note: this is true only for gases at STP, not liquids or solids.) Use the
combined gas law to correct volumes or pressures for non-standard P and T.
8. Know the ideal gas law: PV=nRT , when n= = the number of moles and m= mass of m
M
the gas in grams and M=molar mass of the gas. R=the ideal gas constant (see table 2,
p.454)
9. Know the molar mass formula and the density formula for gases based on the ideal gas
law. This means taking the ideal gas law equation and rearranging it to solve for mass,
m, or density, D= . Using the ideal gas law equation: PV= RT or = = D of a m
V
m
M
m
V RT
PM
gas.
10. Know that at very high pressures, very low temperatures and high molar masses, real
gases behave differently than ideal gases.
11. Know stoichiometry as it relates to balanced equations that contain gases and how to
include the gas laws in those calculations.
Your text specifically gives you examples of volume-volume problems (when T and P do
not need to be accounted for, see p.461) and
volume-mass problems related to gases and stoichiometric calculations.
(Mole-volume relationships are found with balanced chemical equations but masses
need to be converted to moles or volumes before being used in ratios and T and P may
need to be used, also.)