Are you working on a volcano lesson plan? Want to do something more than just the traditional baking soda and vinegar eruption? How about exploring the properties of liquids?
When studying volcanoes, the topics of molten rock, lava flows, lahars, and pyroclastic flows are typically included. Depending upon your lesson plan, you might have a brief mention of how different materials “flow” at differing rates, or how different lavas have different flow properties based upon the silica content. This flow property is called viscosity – i.e. the property of a fluid that resists the forces causing the material to flow.
Everyone has some hands-on knowledge of viscosity. Think about the difference in the flow of water versus maple syrup or motor oil on a cold morning versus a hot day. Yet, we typically don’t do any hands-on science related to this physical property of fluids. An Earth Science – Volcano lesson is a wonderful place to add this hands-on activity.
Now for your recommendations.
From SEED – A laboratory on the Viscosity of Liquids
From the Royal Society of Chemistry – Viscosity
Or, from Sophic Pursuits – Viscosity Explorations
Some safety precautions. Know the materials you are using. The Viscosity Exploration uses dish soap, vegetable oil, corn syrup and water. It also looks at the change in viscosity with temperature. So children need to work with an adult to make sure there are no burns. But, the experiment can be done using ice water, cold water and hot tap water.
Just remember to be safe!