Introduction

Balloons filled with H2, He, and O2 are shown immediately after being inflated and then again in the following lecture.  Differing rates of effusion can be seen.

Rate of effusion for gas 1: rate of effusion for gas 2 = √M2/√M1

(M = molecular or atomic weight)

Inflated balloons
Deflated balloons

To Conduct Demonstration

  1. Show H2, He, and O2 balloons inflated to the same size.
  2. Let them sit undisturbed until the next lecture.  Show again.  Gases effuse out of the balloons according to the size of the gas molecule.

Reaction Time: ~24h