Transcript Chemistry: McMurry and Fay, 5th Edition

Homework Answers
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9.49 – second one has more
9.51 – 1040 L @ STP
9.57 – 167 balloons
9.67 – a) 30.1 amu, b) 26.02 amu
9.71 - 1170 L of gas
Copyright © 2008 Pearson Prentice Hall, Inc.
Chapter 1/1
Partial Pressure
and
Kinetic Theory of
Gases
Copyright © 2008 Pearson Prentice Hall, Inc.
Partial Pressure and Dalton’s
Law
Dalton’s Law of Partial Pressures: The total
pressure exerted by a mixture of gases in a
container at constant V and T is equal to the sum
of the pressures of each individual gas in the
container.
Ptotal = P1 + P2 + … + PN
Mole Fraction (X) =
Moles of component
Total moles in mixture
Xi =
ni
ntotal
or
Xi =
Copyright © 2008 Pearson Prentice Hall, Inc.
Pi
Ptotal
Chapter 9/3
The Kinetic-Molecular Theory
of Gases
1. A gas consists of tiny particles, either atoms or molecules,
moving about at random.
2. The volume of the particles themselves is negligible
compared with the total volume of the gas; most of the volume
of a gas is empty space.
3. The gas particles act independently of one another; there are
no attractive or repulsive forces between particles.
4. Collisions of the gas particles, either with other particles or
with the walls of a container, are elastic (constant
temperature).
5. The average kinetic energy of the gas particles is proportional
to the Kelvin temperature of the sample.
Copyright © 2008 Pearson Prentice Hall, Inc.
Chapter 9/10
The Kinetic-Molecular Theory
of Gases
From assumption 5, the total EK of a mole of particles equals
3RT/2, so the average for 1 molecule is 3RT/2NA =1/2mu2
This rearranges to
Copyright © 2008 Pearson Prentice Hall, Inc.
Chapter 9/23
The Kinetic-Molecular Theory
of Gases
molar
mass
average
speed
Copyright © 2008 Pearson Prentice Hall, Inc.
Chapter 9/24
The Kinetic-Molecular Theory
of Gases
Copyright © 2008 Pearson Prentice Hall, Inc.
Chapter 9/25
H41 – C9
• 9.14 – 9.19, 9.27, 9.31, 9.75, 9.79, 9.81*,
9.87, 9.89, 9.95, 9.97*, 9,101*