Graham's Law

The rate of effusion and diffusion is _______________ proportional to the square root of its' molar mass.

• Directly

• Inversely

• directly and inversely

• cannot be determined

Lighter gases have a ________________ rate of effusion and diffusion.

• faster

• slower

• rate of effusion does not depend on mass.

Effusion is

• used to describe the combustibility of a gas.

• ability of a gas to escape through a tiny opening

• what occurs after diffusion.

• the ability of a gas to mix with other gases.

Identify the factor that determines rates of diffusion and effusion for different molecules at a given temperature.

• Size of the molecules

• Polarity of the molecules

• Temperature of the gas

• Molar mass of the gas

Effusion and diffusion rates are inversely proportional to the square root of the molar mass of the gas.

• True

• False

• neither true or false

Grahams law refers specifically to

• the rate of diffusion only

• the rate of effusion only

• both the rate of diffusion and effusion

• the partial and total pressures of gases in a sample.

How many times faster does He effuse compared to N₂ ? Given:He = 4 g/mol , N₂ = 28 g/mol

• 1.2 times faster

• 2.65 times faster

• 7 times faster

• 0.377 times faster

An example of Effusion

• hole in a balloon

• perfume in air

• smell of a flower

• all of them

Molecules diffuse from

• low to high concentrations

• high to negligible concentrations

• high to low concentrations

• all of them

Which of the following environmental problem is associated with Gas diffusion?

• Air pollution

• Ozone depletion

• Water pollution

• All of them