760 mm Hg

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Needed this week
 Balloons
 One
and two liter bottles
 Cotton gloves (to handle and protect
from dry ice?)
Chapter 13, States of Matter
Four states of matter you
need to know:
Solid
Liquid
Gas
Plasma
Determining the states of
matter
The
amount of kinetic
energy a substance
contains determines its
physical state (solid, gas,
liquid). The more energy it
has, the “looser” it is bound
States of Matter
Adding Kinetic Energy
Notice
Did
you notice that
the Kinetic energy
was added in the
form of heat?
Solids
Solids
stick together and
stay in the same position
next to each other (Like
a class in which all
students are seated)
Liquids
In
a liquid, the
particles touch each
other but can move
freely, like students in a
crowded hallway.
Gases
In
a gas, the molecules are
not in regular contact with
each other and bounce off
when they hit one another
(picture sixth graders in
gym)
Gas Pressure
Gas
pressure is the results of
trillions of molecules
banging against each
other. The pressure is
exerted in all directions at
once. This is how a balloon
or a tire stays inflated.
Gas Pressure
Atmospheric pressure
Atmospheric
pressure is the pull
of gravity on all the gas above
us in the atmosphere.
A Barometer measures this
pressure
At sea level, atmospheric
pressure is 760 mm of mercury,
on Mt. Everest, it is 253 mm of
mercury
Barometer
Measuring pressure
Atmospheres
(atm)
mm of Mercury (mm Hg)
Pascals (Pa)
Kilopascals (because
pascals are tiny) (kPa)
Note =
Dumb ole’ TV and radio
meteorologists use inches of
mercury rather than mm or
kPa!!! One inch is 25.4 mm
760 mm = 29.92 inches
Converting
1atm
equals
760 mm Hg equals
101.3 kPa
1atm = 760 mm Hg = 101.3 kPa
Swapping units
450
kPa X 760 mm Hg = 3400 mm Hg

101.3 kPa
Note that 760 mm Hg and 101.3 kPa
are the same pressure, so you multiply
by one to convert
Standards
STP
= Standard Temperature
and Pressure
273 K (0° Celsius)
standard pressure is 1 atm
 At STP, one mole of gas
occupies 22.4 L
Temperature and Kinetic
Energy
Temperature
is the
Average Kinetic
Energy in a substance
Should you need more and
better explanations:
 http://phet.colorado.edu/en/simulation/st
ates-of-matter (needs java)(animation)
 http://www.chemtutor.com/sta.htm (text)
 http://www.footprintsscience.co.uk/states.htm (animation and
text)
 http://www.youtube.com/watch?v=V9W
YweBA6vA (music Video)
More links
 http://www.youtube.com/watch?v=cBB
mdqti_Kg (student project video)
 http://www.youtube.com/watch?v=vDZh
Ukp30tE (teacher done music video)
Conclusions
 Answers
questions 3-5 on page 389. Click
the sounds icon for my answers
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