Boyle's Law (Qualitative), Demo #10

An illustration of the Spring of the Aire.  The demo simply uses a 50ml plastic syringe mounted in a block of wood.  The air trapped in the syringe supports a lot of weight and is elastic.  The more pressure applied, the smaller the volume becomes.

Boyle's Law (Quantitative), Demo #12

A modified reconstruction of Robert Boyle's J-tube apparatus for investigating the relationship between pressure and volume on an air sample.  One can collect data in front of the class and show that the PxV product is constant to within 0.1%

The Size of One Mole of Gas, Demo #13

A rubber glove is filled with 44g of crushed dry ice (1.0 mol).  The glove is sealed and set aside to allow the solid to sublime.  The glove inflates to the size of a basketball.  The demonstration affords the opportunity for a groan-producing pun.

Gas Diffusion Using Balloons, Demo #19

This demonstration spans two lectures.  One looks at the change in volume of a balloon over a several day period.  A balloon filled with helium gets a lot smaller because the helium atoms diffuse through the elastic faster than air can diffuse in.  A balloon filled with sulfur hexafluoride actually doubles in volume over the same time period because of the low speed of diffusion of the heavy molecules.

Gas Diffusion Through a Porous Cup, Demo #20

A porous cup is attached to a water-filled manometer.  When the space around the cup is filled with gases like methane or helium, the pressure in the cup increases owing to the greater inward diffusion rate of the lighter gases.  The effect is reversed with carbon dioxide.

Kinetic Molecular Theory Demonstrator, Demo #28

We have a mechanical apparatus that can illustrate random particle motion using an overhead projector.