BOYLE’S LAW
LAB 13-1
CC ___
Simulator 13-1
CONCEPT
The Englishman Robert Boyle discovered that the pressure and volume of any confined gas kept
at constant temperature will vary with each other according to the law PV = constant. That is, at
constant temperature, if either the pressure or volume of the gas is allowed to vary, the other
variable also changes so that the product PV remains constant. Boyle trapped a sample of air by
adding mercury to the open end of the tube and measured the resulting change in volume.
OBJECTIVE
Investigate Boyle’s law the relationship between pressure and volume.
MATERIALS
Boyle’s law apparatus
Ring stand
Set of metric masses 500g, 750g, 1kg, 1.5kg
Test tube clamp
PROCEDURE
1. Set up the Boyle’s law apparatus as shown on the right. Caution,
there are two types of clamps, depending on apparatus you have,
one with a stop-cock and the other with a white pinch clamp.
2. Do not over tighten the test tube clamp on the syringe. This could
damage the apparatus.
3. With the stop-cock open pull piston of syringe up to the highest
reading. Record this reading in millilters or cubic centimeters (c.c.)
4. Now close the stop-cock.
5. Hang a 500g mass on the hanger part of the apparatus. Record the
mass and the new reading.
6. Repeat using 750g, 1kg, and 1.5g. Record mass and readings.
DATA
MASS
(kg)
NEWTONS
(N)
FINAL READING
VOLUME
(c.c.)
AREA
2
(m )
PRESSURE
(Pa)
0.50
0.75
1.00
1.50
PHYSICSINMOTION
Pressure – the amount of force that is applied to an area where the force is distributed. The
metric system unit used to describe pressure is the pascal (Pa) which translates to newtons per
square meter. The Symbol pf pressure is p
F
A
Where
p
F  force
A  area
PRE-LAB QUESTION
1. When the piston in the Boyle’s Law apparatus is at rest, what is the relationship between
the pressure of the trapped gas and the pressure on the outside of the piston?
ANALYSIS
1. Plot a graph of the pressure vs. volume (volume on the x-axis).
2. What pattern does the graph of P versus V suggest?
3. Determine the values for 1/volume for each of the volumes calculated. Graph pressure
vs. 1/volume (1/volume on the x-axis).
4. How does your graph of P versus 1/V illustrate Boyle’s law?
5. Why is it important to keep the temperature constant while performing this experiment?
6. Since gases can be highly compressed, what must be true of the spaces between the
molecules?
7. Would you expect a real gas to follow Boyle’s Law under extremely high pressures?
Explain.
8. At what point would the volume be reduced to zero? Explain. Does your data support this?
9. How does the principle of Boyle’s law come into effect in the operation of a bicycle pump?
PHYSICSINMOTION