An easy macroscopic lecture demonstration of the effect of temperature on the rate is to take three glow sticks and three beakers into the lecture. Place beakers side by side. Place room temperature water in one beaker, ice water in the second and very hot water in the third. Place a glow stick in each beaker and ask students to predict what the difference will be. Leave equilibrating while you do something else, then come back and turn off the room lights. Discuss in terms of collisions and chemiluminescence.
To emphasise the quantitative aspect of the first order decay process, you can use a demonstration on the visualizer – take 40 M&Ms and place them face up (the ‘M’ up) in a clear Tupperware container. This is the population at t=0. Ask a student volunteer to come and shake the container (gently) for 3 seconds and remove the M&Ms that are now face down – the remaining population is recorded as t1/2 on a graph.
The ChemBytes website has a sophisticated set of learning resources for chemical equilibrium. Simulations and practice problems are integrated to help students understand the basics.
The ChemBytes website has a sophisticated set of learning objects to help students understand specific fundamental topics such as aqueous solutions. Dissolution and speciation are covered in detail with simulations and visualisations.
A visual demonstration of Le Chatelier’s principle involves the dynamic equilibrium between nitrogen dioxide and dinitrogen tetroxide gases. Fill a gas syringe with an equilibrium mixture of brown NO2 and colourless N2O4. The effect of pressure is shown by compressing the mixture and observing the change in colour intensity. Similarly, the effect of temperature can be shown by heating or cooling the mixture and observing the colour change.
