Behavior of Gases

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Behavior of Gases
Bill Howard Hopkinton Middle School
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We must consider these three properties when
predicting gas behavior

• volume

• temperature

• pressure

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the amount of space that matter fills
Volume
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the measure of the average energy of motion
(T.E.) of the particles of a substance
Temperature
Not all of the particles have the same energy of
motion
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The force pushing on the surface divided by the
area of that surface
Pressure
force area
Pressure
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Gas molecules collide with each other and the
sides of the container
Units of pressure kilopascals (kPa)
atmospheres (atm)
pounds per
square inch (psi)
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Click on this link and select Boyles Law to read
pressure overview and view pressure animation
http//oldmanhonda.com/FlashTutorials/GasLaws.html

X out of web site to return to PowerPoint Dont
hit the back button
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Boyle's law
The relationship between PRESSURE and VOLUME
At a constant temperature, when the volume
increases, pressure decreases.
pressure
volume
volume
pressure
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Boyles law graph
the pressure decreases
Volume and pressure are inversely proportional
As the volume increases
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As the volume decreases
the pressure increases
Temperature is constant
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Click this link for interactive Boyles law
animation
http//www.chem.iastate.edu/group/Greenbowe/sectio
ns/projectfolder/flashfiles/gaslaw/boyles_law.html

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Who cares? Boyles law in the real world
open bottle
pressure
CO2 volume
fizz
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Who cares? Boyles law in the real world
High pressure allows storage of large amounts of
propane
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Who cares? Boyles law in the real world
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High Altitude Balloons
Sea level
High altitude
lower atmospheric pressure
higher atmospheric pressure
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The Bends Decompression Sickness
Nitrogen gas dissolved in the blood expands when
a diver surfaces too quickly.
Analogy What happens to the dissolved CO2 when
you open a Coke?
Click this link to view Navys slide show
http//www.onr.navy.mil/focus/blowballast/animatio
n/sub/boyleslaw.swf
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Charles's law
The relationship between TEMPERATURE and VOLUME
At a constant pressure, when the temperature
increases volume increases.
temperature
volume
volume
temperature
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the volume increases
Volume and pressure are directly proportional
As the temperature increases
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the volume increases.
Pressure is constant
As the temperature increases
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Click this link for interactive Charless law
animation
http//www.chem.iastate.edu/group/Greenbowe/sectio
ns/projectfolder/flashfiles/gaslaw/charles_law.htm
l
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Who cares? Charless law in the real world
One must consider possible temperature changes
when filling a float balloon with helium
What might happen if the air temperature rises
too much?
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Guy-Lussac's law
The relationship between TEMPERATURE and PRESSURE
At a constant volume, when the temperature
increases pressure increases.
temperature
pressure
pressure
temperature
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temperature and pressure are directly proportional
the pressure increases.
pressure
temperature
As the temperature increases
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Who cares? Guy-Lucssacs law in the real world
What might happen if a defective propane tank
gets too hot?
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Who cares? Guy-Lucssacs law in the real world
Proper tire inflation is important!
friction
temperature
YIKES!
pressure
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Gas Laws Recap
Boyle's law
VOLUME
PRESSURE
Charles's law
VOLUME
TEMPERATURE
Guy-Lussac's law
TEMPERATURE
PRESSURE
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Work Cited
http//www.indiana.edu/geog109/topics/10_ForcesW
inds/GasPressWeb/PressGasLaws.htm l
http//oldmanhonda.com/FlashTutorials/GasLaws.html
http//www.gypsyjournal.net/tire20blowout202.jpg

http//www.grc.nasa.gov/WWW/K-12/airplane/aboyle.h
tml
http//chemsite.lsrhs.net/g_gasses/images/Boyles_l
aw_graph.gif
http//wps.prenhall.com/wps/media/objects/476/4883
16/Instructor_Resources/Chapter_11/FG11_11.JPG
http//images.usatoday.com/tech/_photos/wonderques
t/2004/02-06-balloon.jpg
http//liftoff.msfc.nasa.gov/shared/news2003/Mars/
marsflyer3.jpg
http//wine1.sb.fsu.edu/chm1045/notes/Gases/Pressu
re/Gases02.htm
http//www.scuba-doc.com/art-mos3036a.fig1.jpg
http//www.onr.navy.mil/focus/blowballast/animatio
n/sub/boyleslaw.swf
http//www.chem.iastate.edu/group/Greenbowe/sectio
ns/projectfolder/flashfiles/gaslaw/boyles_law.htm
l
http//www.momathome.com/viewfromhome/images/tgivi
ng_spongebob.jpg