Kitchen Science: Lava in a Cup

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Kitchen Science: How to Make Lava in a Cup

Make lava in a cup right in your kitchen. Well, it’s not really lava, but it looks like lava and acts like lava, bubbling up to the surface.

You will need:

  • A glass
  • Water
  • Light colored cooking oil (vegetable, peanut, etc.), 1/4 cup
  • Salt, a few teaspoons
  • Food coloring


  1. Fill the glass about 3/4 full of water.
  2. Add a few drops of food coloring and stir.
  3. Pour the vegetable oil into the glass.
    It should float on the top. Do you know why?  Oil is lighter than water.
  4. Sprinkle a teaspoon of salt into the glass. Add 1 or 2 more teaspoons.
    Do you see the blobs of salt form and bubble up from the bottom of the glass? Why does the salt sink?  Salt is heavier than oil. As the salt sinks, it takes some of the oil with it, then the salt dissolves and floats back to the top of the oil. Isn’t that awesome?

You can try more variations with this experiment. Try it with different types of oil or try adding different substances.  My 5-year-old sprinkled in sugar, pepper and other spices. He added more food coloring and it floated on top the oil for a second, then looked really cool drifting down to the bottom of the glass. All the while he kept asking, “I wonder what will happen if….?”.  That’s exactly the kind of scientific curiosity we are looking to encourage!

You can find all of our hands-on science experiments by visiting the Creekside Learning Science page.

We’re pinning on Pinterest, too, with lots of other science-y mommas on my collaborative board, Hands-On Science.

Kitchen Science from Creekside Learning: Lava in a Cup