Combined Gas Law

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Combined Gas Law
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The Combined Gas Law
When measured at STP, a quantity of gas has a
volume of 500 dm3. What volume will it occupy at
0 oC and 93.3 kPa?
(101.3 kPa) x (500 dm3) (93.3 kPa) x (V2)
273 K
273 K
(101.3) x (500) (93.3) x (V2)
P1 101.3 kPa T1 273 K V1 500 dm3 P2
93.3 kPa T2 0 oC 273 273 K V2 X dm3
V2 542.9 dm3
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The Combined Gas Law
When measured at STP, a quantity of gas has a
volume of 500 dm3. What volume will it occupy at
0 oC and 93.3 kPa?
P2 x V2 T2
P1 x V1 T1
(101.3 kPa) x (500 dm3) (93.3 kPa) x (V2)

273 K
273 K
P1 101.3 kPa T1 273 K V1 500 dm3 P2
93.3 kPa T2 0 oC 273 273 K V2 X dm3
V2 542.9 dm3
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Gay-Lussacs Law

• The pressure and absolute temperature (K) of a
  gas are directly related
• at constant mass volume

Courtesy Christy Johannesson www.nisd.net/communic
ationsarts/pages/chem
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Gay-Lussacs Law

• The pressure and absolute temperature (K) of a
  gas are directly related
• at constant mass volume

Courtesy Christy Johannesson www.nisd.net/communic
ationsarts/pages/chem
6
Combined Gas Law
P T
V T
PV T
k
PV
(BOYLES LAW)
(CHARLES LAW)
(Gay-Lussacs LAW)
(COMBINED GAS LAW)
P1V1T2 P2V2T1
Courtesy Christy Johannesson www.nisd.net/communic
ationsarts/pages/chem
7
The Combined Gas Law
        The Combined Gas Law
        The Combined Gas Law
Keys
http//www.unit5.org/chemistry/GasLaws.html
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Gas Law Calculations
Boyles Law PV k
Charles Law V T
k
P and V change n, R, T are constant
Ideal Gas Law PV nRT
T and V change P, n, R are constant
P, V, and T change n and R are constant
Combined Gas Law PV T
k