Gas Laws

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Gas Laws

• ChemistryMrs. Coyle

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Factors Affecting Gas Pressure

• Number of Moles (Amount of gas)
• As the number of particles increases, the number
  of collisions with the container wall increases.
• Volume
• The smaller the volume, the greater the pressure
  exerted on the container.
• Temperature
• As temperature increases, kinetic energy
  increases, increasing the frequency of collision.
  Thus pressure increase.

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If Mass and Temp are Constant
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If Mass and Pressure are Constant
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Boyles Law

• P1V1P2V2 T constant
• moles constant
• P vs V hyperbola

Isotherm High Temp
P
V
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Charles Law

• V1 V2 P constant
• T1 T2 Moles constant

Isobar
V
T (K)
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Guy-Lussac

• P1 P2 V constant
• T1 T2 moles
  Constant
• isochoric

P
T
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Combined Gas Law

• P1V1 P2V2_
• T1 T2

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Ideal Gas Law P V n R T

• P pressure Pa N/m2
• V volume measured in m3
• n of moles
• T temperature K
• RUniversal gas constant
• 8.314 kPa L / (mol K)
• 0.0821 L atm/(mol K)
• 62.3 mmHg L/(mol K)

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Daltons Law of Partial Pressures

• PtotP1P2.
• Total pressure of a mixture of gases in a
  container is the sum of the individual pressures
  (partial pressures) of each gas, as if each took
  up the total space alone.
• http//www.wwnorton.com/college/chemistry/gilbert/
  tutorials/interface.asp?chapterchapter_08folder
  daltons_law

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Ideal Gas Laws mostly hold at

• Low pressure
• High temperature