Lava Lamp
Grade Level: 2
Strand: Understanding Matter and Energy
Topic: Properties of Liquids and Solids
Specific Expectation:
Investigate, through experimentation, interactions that occur as a result of mixing
and/or dissolving liquids and solids (e.g., salt and water, sand and water), liquids and
liquids (e.g., oil and water), and solids and solids (e.g., salt and sand).
Required Materials:
 Water
 Vegetable oil
 Salt
 Clear glass or graduated cylinder
 Food colouring (optional)
Procedure:
1. Pour water into glass about 2/3 of the way full
2. Make a prediction of what will happen when the oil is combined with the water
3. Add a layer of oil to the glass (the oil will float on top) and compare to the
prediction
4. Make a prediction of what will happen when salt is added to the water and oil
5. Add salt in small clumps into the glass
6. Observe what happens and compare to the prediction
What you will see:
When the salt is put into the mixture, bubbles sink down to the bottom of the glass
and then rise again, resembling a lava lamp.
Scientific Explanation:
Density - Measurement of how much a given volume of something weighs.
The oil floats on top of the water because water is denser than oil. The salt is a solid
and is denser than both the oil and the water; therefore it sinks to the bottom of the
mixture. On its way down, oil attaches to it, making a “bubble.” The salt then
dissolves in water. As the salt dissolves, the oil is released and floats back up to the
top of the glass.
References:

http://www.exploratorium.edu/science_explorer/volcano.html

http://curriculalessons.suite101.com/article.cfm/chemistry_experiments_invo
lving_solutions
Opportunities and other Considerations:

Adding food colouring to the water adds an extra effect

Students can try this experiment themselves and change the different
variables including, water temperature, and try in a bottle or jar and shake
Names of Presenters: Jennifer Page and Jacqueline Holland – PJ1