Effusion and Diffusion (5.3.2)

Question 1

• Effusion is the process by which particles of a gas escape their container through a very small hole.

Answer 1

• Effusion is the process by which particles of a gas escape their container through a very small hole.

Question 2

• Diffusion is the process by which particles travel through molecules of a different substance or a semipermeable membrane.

Answer 2

• Diffusion is the process by which particles travel through molecules of a different substance or a semipermeable membrane.

Question 3

Effusion is the process by which particles of a gas
escape their container through a very small hole.

The rate of effusion is governed by Graham’s law
of effusion. Graham’s law of effusion states that
the ratio of the rates of effusion of two gases is
equal to the ratio of their root-mean-square
speeds. Since the root-mean-square speed is the
square root of 3RT/M, Graham’s law of effusion can
be expressed in terms of the molecular masses
(M) of the two gases.

By Graham’s law of effusion, lighter particles have
higher root-mean-square speeds, and therefore
diffuse faster. This is why helium balloons deflate
more quickly than air-filled balloons.

Answer 3

Effusion is the process by which particles of a gas
escape their container through a very small hole.

The rate of effusion is governed by Graham’s law
of effusion. Graham’s law of effusion states that
the ratio of the rates of effusion of two gases is
equal to the ratio of their root-mean-square
speeds. Since the root-mean-square speed is the
square root of 3RT/M, Graham’s law of effusion can
be expressed in terms of the molecular masses
(M) of the two gases.

By Graham’s law of effusion, lighter particles have
higher root-mean-square speeds, and therefore
diffuse faster. This is why helium balloons deflate
more quickly than air-filled balloons.

Question 4

Diffusion is the process by which particles travel
through molecules of different substances or a
semipermeable membrane. As with effusion, lighter
particles diffuse more rapidly than heavier particles.

Ammonia (NH3), for example, is lighter than
hydrogen chloride (HCl). When placed at opposite
ends of a tube, the NH3 molecules diffuse faster
than the HCl molecules, and thus travel further in
the same amount of time.

Answer 4

Diffusion is the process by which particles travel
through molecules of different substances or a
semipermeable membrane. As with effusion, lighter
particles diffuse more rapidly than heavier particles.

Ammonia (NH3), for example, is lighter than
hydrogen chloride (HCl). When placed at opposite
ends of a tube, the NH3 molecules diffuse faster
than the HCl molecules, and thus travel further in
the same amount of time.

Question 5

What does semipermeable mean?

Answer 5

Allowing some molecules to pass through, but not others.