-Diffusion -Graham

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-Diffusion -Grahams Law of Effusion-Daltons
Law of Partial Pressures

• Chemistry
• Mrs. Coyle

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Diffusion
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Diffusion

• The process in which particles of matter move
  from areas of high concentration to areas of low
  concentration.

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Effusion

• The passage of gases through a small hole or
  pores of a membrane.

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Note

• Gases of lower molar mass diffuse and effuse
  faster than gases of higher molar mass.

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Grahams Law of Effusion

• ________
• va v (MMb ) vb MMa
• v rate of effusionMM molar mass
• -The rate of effusion of a gas is inversely
  proportional to the square root of its molar
  mass.

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Example

• Compare the rates of effusion of CO2 to oxygen
  gas.

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Daltons Law of Partial Pressures
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Daltons Law of Partial Pressures

• The total pressure in a gas mixture is the sum of
  the partial pressures of each individual gas.
• Ptotal Pgas 1 Pgas 2 Pgas 3

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Partial Pressure of a Gas

• The pressure that the gas would exert if it were
  the only gas present in the container.