Download ______ Chapter 10, Practice A, page 338 Name Period

Chapter 10, Practice A, page 338
These practice problems require the use of the formula(s)
W  PV
1. Gas in a Dingyu’s lung is at pressure of 1.6 x 105 Pa and a volume
of 4.0 m3. What is the work done by the gas if
a. It expands at constant pressure to twice its initial volume
before his lungs pops?
_____________________ _______
Name
Period

1st determine what you need to find
2nd determine what variable each
number is.
3rd determine which equation to use.
4th solve the equation
b. As he scuba dives under 50.0 meters of water, what is the volume
of his lung, if it is compressed at
constant pressure to one-quarter of its initial volume?
2. A gas is enclosed in a container fitted with a piston. The applied pressure is maintained at 599,500 Pa as the
piston moves inward, which changes the volume of the gas from 5.317 x 10-4 m3 to 2.523 x 10-4 m3. How
much work is done? Is the work done on or by the gas? Explain your answer.
3. James, the clown, inflates a balloon with helium at a constant pressure that is 4.3 x 105 Pa in excess of
atmospheric pressure. If the balloon inflates from a volume of 1.8 x 10-4 m3 to 9.5 x 10-4 m3, how much work
is done on the surrounding air by the helium-filled balloon during this expansion?
4. Steam moves into the cylinder of a steam engine at a constant pressure and does 0.84 J of work on a piston.
The diameter of the piston is .016 m, and the piston travels .021 m. What is the pressure of the steam?
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Chapter 10, Section 1 Review, page 341
These practice problems require the use of the formulas
W  PV
1. In which of the situations listed below is energy being transferred
as heat to the system in order for the system to do work?
a. Sharon rubs two sticks are rubbed
together to start a fire.

1st determine what you need to find
2nd determine what variable each number is.
3rd determine which equation to use.
4th solve the equation

b. A firecracker explodes in Patricks hand during July 4th.
c. A red-hot iron bar is set aside by Mireya to cool.
2. A mixture of gasoline vapor and air is placed in an engine cylinder. The piston has an area of 7.4 x 10-3 m2
and is displaced inward by 7.2 x 10-2 m. If the 9.5 x 105 Pa of pressure is placed on the piston, how much
work is done during this process? Is work being done on or by the gas mixture?
3. Isabella hangs onto the side of a weather balloon slowly expands as energy is transferred as heat from the
outside air. If the average net pressure is 1.5 x 103 Pa and the balloon’s volume increase by 5.4 x 10-5 m3,
how much work is done by the expanding gas?
4. Identify the following processes as isothermal, isovolumetric, or adiabatic:
a. A tire being rapidly inflated by Marleen.
b. A Shane’s lung expanding gradually at a constant temperature
c. A steel tank of gas being heated by Anthony before it explodes.
Warmups
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Chapter 10, Section 2 Practice B, page 346
These practice problems require the use of the formulas:
U  Q  W

1st determine what you need to find
2nd determine what variable each number is.
1. Heat is added to a system, and the system does 26 J of work. If
the internal energy increases by 7 J, how much heat was added to
the system?
3rd determine which equation to use.
4th solve the equation

2. The internal energy of the gas in a gasoline engine’s cylinder decreases by 195 J. if 52.0 J of work is done by
the gas, how much energy is transferred as heat? Is this energy added to or removed from the gas?
3. A 2.0 kg quantity of water is held at constant volume in a pressure cooker and heated by a range element.
The system’s internal energy increases by 8.0 x 103 J. However, the pressure cooker is not well insulated,
and as a result, 2.0 x 103 J of energy is transferred to the surrounding air. How much energy is transferred
from the range element to the pressure cooker as heat?
4. The internal energy of a gas decreases by 344 J. If the process is adiabatic, how much energy is transferred
as heat? How much work is done on or by the gas?
5. A steam engine’s boiler completely converts 155 kg of water to steam.
This process involves the transfer of 3.50 x 108 J as heat. If steam escaping
through a safety valve does 1.76 x 108 J of work expanding against the
outside atmosphere, what is the net change in the internal energy of the
water-steam system?
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Chapter 10, Section 2 Review, page 349
1. Use the first law of thermodynamics to show that the internal
energy of an isolated system is always conserved.

1st determine what you need to find
2nd determine what variable each number is.
3rd determine which equation to use.
4th solve the equation
2. In the systems listed below, identify where energy is transferred
as heat and work and where changes in internal energy occur. Is

energy conserved in each case?
a. The steam in a steam engine consisting of a boiler, a firebox, a cylinder, a piston, and a flywheel.
__________ __________ __________ __________ __________
b. The drill bit of a power drill and a metal block into which a hole is being drilled.
3. Does the system’s overall internal energy increase, decrease or remain unchanged in part b of item 2?
Explain your answer in terms of the first law of thermodynamics.
4. A compressor for Megan’s jackhammer expands the air in the hammer’s cylinder at a constant pressure of
8.6 x 105 Pa. the increase in the cylinder’s volume is 4.05 x 10-4 m3. During the process, 9.5 J of energy is
transferred out of the cylinder as heat.
a. What is the work done by the air?
b. What is the change in the air’s internal energy?
c. What type of ideal thermodynamic process does this approximate?
5. A mixture of fuel and air is enclosed in an engine cylinder fitted with a piston. The gas pressure is maintained
at 7.07 x 105 Pa as the piston moves slowly inward. If the gas volume decreases by 1.1 x 10-4 m3 and the
internal energy of the gas increases by 62 J, how much energy is added to or removed from the system as
heat?
6. If Jocelyn’s weather balloon in flight gives up 15 J of energy as heat and the gas within it does 13 J of work
on the outside air, by how much does its internal energy change
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Chapter 10, Section 3 Review, page 357
1.
Is it possible to construct a heat engine that doesn’t transfer
energy to its surroundings? Explain.

1st determine what you need to find
2nd determine what variable each number is.
3rd determine which equation to use.
4th solve the equation
3.
Which of the following systems have high entropy?
Which systems have low entropy?
a.
Papers scattered randomly across a desk
b.
Papers organized in a report
c.
A freshly opened pack of cards
d.
A mixed deck of cards
e.
A room after a party
f.
A room before a party
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4.
Some compounds have been observed to form spontaneously, even
though they are more ordered than their components. Explain how this is
consistent with the second law of thermodynamics.
5.
Discuss three common examples of natural processes that involve decreases in entropy. Identify the
corresponding entropy increases in the environments of these processes.
6.
A steam-driven turbine is one major component of an electric power plant. Why is it advantageous to
increase the steam’s temperature as much as possible?
Chapter 10, Review, page 360
2.
In what two ways can the internal energy of a system be increased?
5. When an ideal gas expands adiabatically, it does work on its surroundings. Describe the various transfers of
energy that take place.
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9.
How much work is done when a tire’s volume increases from 35.25 x 10-3 m3 to
39.47 x 10-3 m3 at a pressure of 2.55 x 105 Pa in excess of atmospheric pressure?
Is work done on or by the gas?
11.
Write the equation for the first law of thermodynamics, and explain why it is an expression of energy
conservation.
14.
A bomb calorimeter is placed in a water bath, and a mixture of fuel and oxygen is burned inside it. The
temperature of the water is observed to rise during the combustion reaction. The calorimeter and the water
remain at constant volume.
 If the reaction products are the system, which thermodynamic quantities―U, Q, or W―are positive
and which are negative?

If the water bath is the system, which thermodynamic quantities―U, Q, or W―are positive and which
are negative.
16.
Heat is added to an open pan of water at 100.0C, vaporizing the water. The expanding steam that
results does 43,000 J of work, and the internal energy of the system increases by 604,000 J. How much energy is
transferred to the system as heat?
20.
In which of the following systems is entropy increasing? (Do not include the surroundings as part of the
system.)
 Jonathan breaks an eggs and scrambles it.
 Reese’s cluttered room is cleaned and organized by his mom.
 A thin stick is placed in a glass of sugar-saturated water, and sugar crystals form on the stick.
24.
A salt solution is placed in Jessica’s bowl and set in sunlight. The salt crystals that remain after the water
has evaporated are more highly ordered than the randomly dispersed sodium and chloride ions in the solution.
Has the requirement that total entropy increase been violated? Explain your answer.
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