Ch. 9 Flashcards
(28 cards)
The average distance a molecule travels between collisions.
Mean free path
Increases with decreasing pressure.
Mean free path
Movement of an atom or molecule from a region of relatively high concentration to one of relatively low concentration.
Diffusion
Rate of diffusion =
Amount of gas passing through an area
βββββββββββββββ
Unit of time
The increase or decrease in concentration from one point to another.
Concentration gradient
Transfer of gaseous atoms or molecules from a container to a vacuum through a very small hole/opening.
Effusion
Grahamβs law of effusion:
The rate of effusion of a gas is inversely proportional to the square root of the mass of its particles.
Rate of effusion 1/square root of mass
Gas molecules are very ______
Compared to the distances between them.
Small
Gas molecules which collide with the walls of the container are the cause of the _______ exerted by the gas.
Pressure
Gas molecules are in _____ __________.
Continuous motion
Daltonβs law of partial pressures:
The total pressure of a mixture of ideal gases is equal to the sum of the partial pressures of the component gasses.
P. = P. + P + P
Total A. B. C
Force exerted per unit area.
Pressure
P = F
β
A
Pressure can be increased by increasing the amount of _______ or by decreasing the _______.
Force
Area
SI unit of pressure
Pascal (Pa)
1 Pa = 1 N/m^2
Temperature at which the volume of a gas would be zero according to Charlesβs law.
Absolute zero
Process whereby gas molecules spread out in response to a concentration gradient.
Diffusion
Process whereby gas escapes from a container into a vacuum through a small hole.
Effusion
The pressure due to any individual component in a gas mixture is called ___________ _____________.
Partial pressure
Device used to measure atmospheric pressure.
Barometer
Ratio of the experimentally measured molar volume for a gas to its molar volume as computed from the ideal gas equation.
compressibility factor (Z)
Pressure exerted by a fluid due to gravity.
hydrostatic pressure
Hypothetical gas whose physical properties are perfectly described by the gas laws.
ideal gas
Theory based on simple principles and assumptions that effectively explains ideal gas behavior.
kinetic molecular theory
Device used to measure the pressure of a gas trapped in a container.
manometer