Question

derive an expression for mean free path of gas molecules

Answer 1

Answer:

$\large\mathbb{\underbrace\purple{ANSWER}}$

The mean free path is the distance that a molecule travels between collisions. The criterion is: λ (N/V) π r² ≈ 1, where r is the radius of a molecule. ...

MARK AS BRAINLIEST

Answer 2

Answer:

The mean free path is the distance that a molecule travels between collisions.

The mean free path is determined by the criterion that there is one molecule within the "collision tube" that is swept out by a molecular trajectory.

The criterion is: λ (N/V) π r2 ≈ 1, where r is the radius of a molecule.

This gives: λ = 1 / [(N/V) π r2]

Numerical estimates

Molecular cross-sectional area: π r2 ≈ 10-19 m2

Molecular density (sea level): N/V = P/kT ≈ 3 x 1025 molecules/m3

Mean free path (sea level): &lambda ≈ 10-7m ≈ hundreds of molecular diameters