To Do…
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Discussion tomorrow.
LonCapa Exam Review (due Friday,
February 14 by 7 pm)
Exam Tuesday, February 18
1
Exam 1
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Tuesday, February 18; 7:00 pm – 8:30
pm; 114 David Kinley Hall (DKH)
Conflict: 2/18; 5:00 pm – 6:30 pm;
140 Burrill (sign up outside of 101 CA)
All free response.
See me right away if you have a
conflict with the exam and conflict
times.
2
Exam 1 Reviews
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Saturday, 2/15, 140 Burrill Hall, 1:002:50 pm (Tracey and Jonathan)
Sunday, 2/16, 161 Noyes Lab; 4:005:20 pm (Ryan and Ina)
3
Egg in a Bottle
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Using liquid nitrogen to cool the bottle.
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What factors are changing?
What factors are staying constant?
Placing a flame in the bottle.
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What factors are changing?
What factors are staying constant?
4
Clicker Question
You are holding three balloons each containing
an equal mass of a different gas. The balloon
containing which gas is the largest balloon?
a) H2
b) He
c) O2
d) All have the same volume.
5
Clicker Question
You are holding three balloons each containing
an equal mass of a different gas. The balloon
containing which gas is the largest balloon?
a) H2
b) He
c) O2
d) All have the same volume.
6
Clicker Question
You are holding two 4.50-L balloons, one with
helium gas and one with SF6 gas, both at 1.00 atm
and 25°C. In which balloon is there a greater
number of moles of gas?
a) The balloon filled with helium gas.
b) The balloon filled with SF6 gas.
c) The balloons contain an equal number of
moles of gas.
7
Clicker Question
You are holding two 4.50-L balloons, one with
helium gas and one with SF6 gas, both at 1.00 atm
and 25°C. In which balloon is there a greater
number of moles of gas?
a) The balloon filled with helium gas.
b) The balloon filled with SF6 gas.
c) The balloons contain an equal number of
moles of gas.
8
Clicker Question
You are holding two 4.50-L balloons, one with
helium gas and one with SF6 gas, both at 1.00 atm
and 25°C. In which balloon is there a greater
mass of gas?
a) The balloon filled with helium gas.
b) The balloon filled with SF6 gas.
c) The balloons contain an equal mass of gas.
9
Clicker Question
You are holding two 4.50-L balloons, one with
helium gas and one with SF6 gas, both at 1.00 atm
and 25°C. In which balloon is there a greater
mass of gas?
a) The balloon filled with helium gas.
b) The balloon filled with SF6 gas.
c) The balloons contain an equal mass of gas.
10
Gas Law Problems
You are holding two 4.50-L balloons,
one with helium gas and one with SF6
gas, both at 1.00 atm and 25°C.
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Determine the number of moles of
each gas. (0.184 mol)
Determine the mass of each gas.
(26.9 g SF6, 0.736 g He)
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Gas Law Problem
What happens to a 4.50-L balloon
at 25.0C and 1.00 atm if you heat
it to 95.5C ?
Solve for the new condition.
(V2=5.56L)
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Gas Law Problem
What happens to a 4.50-L steel tank
of gas at 25.0C and 1.00 atm if you
heat it to 95.5C ?
Solve for the new condition.
(P2=1.24 atm)
13
Clicker Question
You have a certain mass of He gas in a rigid steel
container. You add the same mass of Ne gas to this
container at constant temperature. Which of the
following best describes what happens?
a) The pressure in the container doubles.
b) The pressure in the container increases but the
increase is less than double.
c) The pressure in the container more than
doubles.
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Clicker Question
You have a certain mass of He gas in a rigid steel
container. You add the same mass of Ne gas to this
container at constant temperature. Which of the
following best describes what happens?
a) The pressure in the container doubles.
b) The pressure in the container increases but the
increase is less than double.
c) The pressure in the container more than
doubles.
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The Partial Pressure of each Gas in a Mixture of
Gases in a Container Depends on the Number
of Moles of that Gas
Gas Law Problem
Consider a sample of gas at 2.00 atm
in a 35.0-L container at 25.0C . You
transfer all of the gas to a 70.0-L
container and you heat the gas to
50.0C.
Determine the new pressure of the
gas. (P2=1.08 atm)
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Clicker Question
As you increase the temperature of a sample
of gas at constant pressure and volume, what
happens to the number of moles of gas?
a) The number of moles of gas increases.
b) The number of moles of gas decreases.
c) The number of moles of gas does not
change.
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Clicker Question
As you increase the temperature of a sample
of gas at constant pressure and volume, what
happens to the number of moles of gas?
a) The number of moles of gas increases.
b) The number of moles of gas decreases.
c) The number of moles of gas does not
change.
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