On a hot summer day, the temperature is 40.0C and the pressure is ...

[anjilletteb]

On a hot summer day, the temperature is 40.0C and the pressure is 1.01  105 Pa.
 
  Let us model the air as all nitrogen of molecular mass 28.0 g/mol having molecules of diameter
  0.500 nm that are moving at their root-mean-square speed. Avogadro's number is
  6.02  1023 molecules/mol, the ideal gas constant is 8.31 J/mol  K, and the Boltzmann constant is 1.38  10-23 J/K. Calculate reasonable estimates for
  (a) the root-mean-square speed of the nitrogen molecules.
  (b) the average distance a typical molecule travels between collisions.
  (c) the average time a molecule travels between collisions, assuming that the molecules are moving at their root-mean-square speeds.
  (d) the number of collisions an average molecule undergoes per second.
  What will be an ideal response?

Question 2

The mean free path of an oxygen molecule is 2.0  10-5 m, when the gas is at a pressure of 120 Pa and a temperature of 275 K.
 
  The molecular mass of oxygen is 32.0 g/mol and the Boltzmann constant is 1.38  10-23 J/K, Avogadro's number is 6.02  1023 molecules/mole, and the ideal gas constant is R = 8.314 J/mol  K = 0.0821 L  atm/mol  K. Assuming that the molecules are moving at their root-mean-square speeds, the average time interval between collisions of an oxygen molecule is closest to
  A) 20 ns.
  B) 43 ns.
  C) 95 ns.
  D) 200 ns.
  E) 420 ns.

[connor417]

Answer to Question 1

Answer:
(a) 528 m/s (b) 3.85  10-8 m
(c) 7.29  10-11 s (d) 1.37  1010 collisions

Answer to Question 2

Answer: B

[anjilletteb]

Excellent

[raili21]

Gracias!