boyles law 1 atm 4 liters as the pressure on a gas increases 2 atm 2 liters as the pressure on a gas...
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Boyle’s Law
1 atm
4 Liters
• As the pressure on a gas increases2 atm
2 Liters
• As the pressure on a gas increases -
the volume decreases
• Pressure and volume are inversely related
Boyle’s Law
Timberlake, Chemistry 7th Edition, page 253
Boyle’s Law
Timberlake, Chemistry 7th Edition, page 253
P1V1 = P2V2
(Temperature is held constant)
P vs. V (Boyle’s law)
At constant temperature and amount of gas, pressuredecreases as volume increases (and vice versa).
Copyright © 2007 Pearson Benjamin Cummings. All rights reserved.
P1V1 = P2V2
Copyright © 2007 Pearson Benjamin Cummings. All rights reserved.
DigitalText
DigitalText
Boyle's Law
If n and T are constant, then
PV = (nRT) = kPV = (nRT) = k
This means, for example, that Pressure goes up as Volume goes down.
Robert Boyle(1627 - 1691)
Son of Early of Cork, Ireland.
A bicycle pump is a good example of Boyle's law.
As the volume of the air trapped in the pump isreduced, its pressure goes up, and air is forcedinto the tire.
• As the pressure on a gas increases
• As the pressure on a gas increases -
the volume decreases
• Pressure and volume are inversely related
1 atm
4 Liters
2 atm
2 Liters
• As the pressure on a gas increases -
the volume decreases
• Pressure and volume are inversely related
2 atm
2 Liters
Boyle’s Law Data
Pressure-Volume Relationship
2.5
250
200
150
100
50
0 0.5 1.0 1.5 2.0
Volume (L)
Pre
ssur
e (k
Pa)
(P1,V1)
(P2,V2)
(P3,V3)
P1 x V1 = P2 x V2 = P3 x V3 = 100 L x kPa
P1 = 100 kPaV1 = 1.0 L
P2 = 50 kPaV2 = 2.0 L
P3 = 200 kPaV3 = 0.5 L
P vs. V (Boyle’s Data)
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 404
Pressure vs. Volume for a Fixed Amount of Gas
(Constant Temperature)
0 100 200 300 400 500
Pressure Volume PV
(Kpa) (mL)
100 500 50,000
150 333 49,950
200 250 50,000
250 200 50,000
300 166 49,800
350 143 50,500
400 125 50,000
450 110 49,500
Vol
ume
(mL)
100
200
300
400
500
600
Pressure (KPa)
Pressure vs. Reciprocal of Volume for a Fixed Amount of Gas
(Constant Temperature)
0 100 200 300 400 500
Pressure Volume 1/V
(Kpa) (mL)
100 500 0.002
150 333 0.003
200 250 0.004
250 200 0.005
300 166 0.006
350 143 0.007
400 125 0.008
450 110 0.009
1 /
Vol
ume
(1/L
)
0.002
0.004
0.006
0.008
0.010
Pressure (KPa)
Boyle’s Law Illustrated
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 404
The pressure and volume of a gas are inversely related
•at constant mass & temp
Boyle’s Law
P
V
PV = kCourtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem
Volume(mL)
Pressure(torr)
P.V(mL.torr)
10.0
20.0
30.0
40.0
760.0
379.6
253.2
191.0
7.60 x 103
7.59 x 103
7.60 x 103
7.64 x 103
Pressure and Volume of a GasBoyle’s LawBoyle’s Law
A quantity of gas under a pressure of 106.6 kPa has a volumeof 380 dm3. What is the volume of the gas at standard pressure, if the temperature is held constant?
P1 x V1 = P2 x V2
(106.6 kPa) x (380 dm3) = (103.3 kPa) x (V2)
V2 = 400 dm3
PV Calculation (Boyle’s Law)
A quantity of gas has a volume of 120 dm3 when confined under a pressure of 93.3 kPa at a temperature of 20 oC. At what pressure will the volume of the gas be 30 dm3 at20 oC?
P1 x V1 = P2 x V2
(93.3 kPa) x (120 dm3) = (P2) x (30 dm3)
P2 = 373.2 kPa
Volume and Pressure
Two-liter flask
One-liter flask
The molecules arecloser together; thedensity is doubled.
The average molecules hits the wall twice as often. The total number of impacts with the wall is doubled and the pressure is doubled.
Bailar, Jr, Moeller, Kleinberg, Guss, Castellion, Metz, Chemistry, 1984, page 101
Volume and Pressure
Two-liter flask
The molecules arecloser together; thedensity is doubled.
The average molecules hits the wall twice as often. The total number of impacts with the wall is doubled and the pressure is doubled.
One-liter flask
Bailar, Jr, Moeller, Kleinberg, Guss, Castellion, Metz, Chemistry, 1984, page 101
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