We all know that oil and water don’t mix. But did you know that you can use the two liquids’ non-compatibility to create a beautiful science experiment? With a few basic kitchen supplies and a playing card, you can put together an eye-catching homemade lava lamp – and learn more about how oil and water interact along the way!
2 identical tall glasses (make sure they’re identical!)
1 playing card
Fill one glass with vegetable oil to the brim.
Into the other glass, add a few drops of food coloring. Then fill the glass with water to the brim.
Cover the glass containing water and food coloring with the playing card.
Carefully pick up the glass of water and food coloring, keeping the opening covered with the playing card, and stack it upside-down on the glass containing oil, aligning the rims as exactly as you can.
Carefully remove the playing card. Watch as the water, because it’s denser than oil, falls down into the other glass and creates a lava lamp effect.
To further demonstrate the properties of oil and water, repeat the experiment in reverse, stacking the glass of oil on top of the glass containing the water and food coloring. Note how the oil, because it’s less dense than water, does not fall into the other glass and instead stays put.