Transcript Gas pressure & volume p X V = Constant  For example, suppose we have a theoretical gas confined in a jar with.

Gas pressure & volume
p X V = Constant

For example, suppose we have a theoretical gas
confined in a jar with a piston at the top. The
initial state of the gas has a volume equal to 4.0
cubic meters and the pressure is 1.0 kilopascal.
With the temperature and number of moles held
constant, weights are slowly added to the top of
the piston to increase the pressure. When the
pressure is 1.33 kilopascals the volume
decreases to 3.0 cubic meters. The product of
pressure and volume remains a constant (4 x
1.0 = 3 x 1.33333 ).
Given below is the experimental data of specific amount of
a fixed mass of gas at constant temperature
 P(atm)

p1 = 1
 p2 = 2
 p3 = 4
volume(cm3)
V1 = 8
V2 = 4
V3 = 2
p X V(atmXcm3)
1 X8 = 8
2X4=8
4X2=8
Boyle’s Law
For a fixed mass of gas, at constant temperature:
p V = constant
p1V1 = p2V2
Or
Volume is inversely proportional to pressure
V  1/p
Solve
 An
exhaust pump is connected to a flask
of volume 100 cm3. The volume swept out
by the piston is 25 cm3 for each stroke.
The pressure in the vessel is originally 1
atm.
By considering one stroke at a time, find
the pressure in the vessel after two
strokes.
solve

i)
ii)
A 6 litre container of gas has a pressure
of 8.2 atm.
Calculate the new volume occupied by
the gas if the pressure is reduced by 3
atm at the same temperature.
What will be the new volume if the
pressure is reduced to 4 atm in the given
example?
This powerpoint was kindly donated to
www.worldofteaching.com
http://www.worldofteaching.com is home to over a
thousand powerpoints submitted by teachers. This is a
completely free site and requires no registration. Please
visit and I hope it will help in your teaching.