To do
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4th HW assignment due Friday, 2/27, 10 pm.
It is open now.
3rd Quiz Friday, 2/27 in Discussion.
Read Chapter 6.1-6.2 and do text HW for
Thursday.
1
PV/nT for Different Gases
(all at 1 atm and 273K)
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O2:
N2:
CO2:
NH3:
Ar:
0.082040
0.082059
0.081538
0.080875
0.082040
Latm/molK
Latm/molK
Latm/molK
Latm/molK
Latm/molK
2
Kinetic Molecular Theory
Gases consist of particles in
constant random motion.
 Temperature is a measure of
average kinetic energy.
 Pressure is due to collisions of
gas particles with the
container.
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3
Gas Law Problem
You heat 5.00-g of KClO3. Determine
the volume of oxygen gas collected at
1.00 atm and 25°C.
KClO3 (s)  KCl (s) + O2 (g)
4
The Partial Pressure of each Gas in a Mixture of
Gases in a Container Depends on the Number
of Moles of that Gas
KMT (assumptions)
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Assume gas particles exert no
forces on each other.
Assume the volume of the
individual gas particles is
negligible (zero).
6
PV/nRT vs. P
7
Clicker Question
You have two 4.50-L containers at 25°C, one with
1.0 mol helium gas and one with 1.0 mol SF6 gas.
In which container is there a greater pressure?
a) The container filled with helium gas. The
atoms are faster and hit more often.
b) The container filled with SF6 gas. The
molecules are heavier and hit with more force.
c) The gases in the containers exert equal
pressure.
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