We're going to watch how density works by making a simple lava lamp that doesn't need electricity! If you like to watch blob-type shapes shift and ooze around, then this is something you're going to want to experiment with.  but don't feel that you have to use the materials mentioned below - feel free to experiment with other liquids you have around the house, and be sure to let me know what you've found in the comment section below.

All you need is about 10 minutes and a few quick items you already have around the house.  Are you ready?

Please login or register to read the rest of this content.

Have a question ?

Tell us what you're thinking...


37 Responses to “Lava Lamp”

  1. It is best to use vegetable oil. Canola oil does not work nearly as well.

  2. lorenavcolon says:

    Can I use canola oil instead?

  3. Feel free to try this experiment with olive oil, but it most likely won’t work as well as vegetable oil.

  4. jtavoight4 says:

    Can you use olive oil instead of vegetable oil

  5. When a substance is soluble, that means it can be dissolved in a liquid, especially water.

  6. jocelyngelms says:

    what is soluble

  7. Marianne Reed says:

    I like that if you put the oil on top of the water, add the salt and then add blue food coloring drops to the oil surface, if you look directly down on the surface of the water (through the oil) you see sparkles that look like the night sky full of stars.
    From: Sky

  8. Then it won’t be colored! 🙂 It will still work though.

  9. Maricelli Pena says:

    thats really cool !! but what if i don’t put food dye

  10. Patti Heilmann says:

    cool awesome

  11. Audrey Bernier says:

    Nvm works really well!

  12. Audrey Bernier says:

    Does sugar work?

  13. Michelle Stevens says:

    I have a lava lamp night-light but the lava is plastic and won’t move.

  14. Amy Alexanian says:

    pepper is really cool

  15. Amy Alexanian says:


  16. Peter Richter says:

    one of the coolest ones yet !!!!!!!!!!!

  17. Becky Ulrick says:

    So AWESOME!!!!

  18. Rebecca Barth says:

    We put everything in this and made several. Even my 4 year old helped! We loved it! My son even had glow in the dark dye from a slime kit. We put that in the lava lamp, and it was so cool in the dark with a flashlight shining through it!

  19. nicolas segonne says:

    Try pepper and sugar! Very cool!

  20. Martin Melody says:


  21. Kristi Eth says:

    Thx for the tip I will test it out once we get the materials.
    oldest son-Justin (13)

  22. Michelle Garcia says:

    hey guys try puting the cap of the jar on and put it up side down!!!!!!

    Mia G. age 8

  23. Lillian Jackson says:

    If you go into a dark room and shine a flashlight through the bottom then add alka-seltzer it looks like one you buy at the store!

  24. Melissa Wilson says:

    It’s awesome! It totally worked! (Noah, age 7)

  25. Alysia Humphries says:

    I always thought Lava Lamps were just normal lamps with the glass colored in a way that it would look like lava.

  26. The food coloring contains water. Water is what allows you to squirt food coloring where you want it. It carries the color….that’s a good way to think of it. Water and oil, simply put, don’t mix.

    But why don’t they mix? Is oil just being mean or something?
    Oil and water are chemically very different from one another. Oil is made up of very long molecules that do not attract other molecules well. Water usually bonds well with other molecules due to its short molecules with positively and negatively charged ends that are very anxious to bond with something, almost anything. Also, oil molecules are very large and water molecules are very small. All these differences are the main reasons that oil and water don’t mix.
    Water birds like ducks and geese are covered with feathers that soak up water like a sponge, but they can swim around in water and not drown. How is that possible? The birds have a gland on their bodies that contains oil. The birds use their beaks to transfer this oil to the feathers that will come in contact with the water. Since water and oil don’t mix, the oil makes a barrier that keeps the water off the feathers.

    Oil is slippery because of two main reasons. As I stated before, oil molecules are long and large. They do not bond easily with anything because they are satisfied with themselves the way they are…not looking for any company, no friends. Another reason oil is slippery is because it has a very high surface tension. It is hard for most substances to break the surface tension of oil in the first place, and then the substance has to deal with oil’s unfriendliness in bonding with other substances. So, oil slides around instead of grabbing ahold of anything because it….well, it just wants to be alone, I guess.

  27. Jannelle Nevels says:

    We loved the experiment!! My kids would like to know: Why doesn’t the food coloring dissolve in the oil? Why is oil so slippery?

  28. Sounds like you were not logged in.. and also sounds like you figured it out? Let me know if you still have trouble!

  29. Debra Thomson says:

    The lamp looks REALLY cool when you add clear water, oil and salt, then add food coloring.
    Holly Thomson,12

  30. Debra Thomson says:

    When I try to watch this video, it says, video not found or access denied. Is there anything you can do to fix that?

    Holly Thomson

  31. They use different kinds of liquids and heat to change the densities of the oils. And they want to sell you one, so they look cool. 🙂

  32. Sheila Jakobsen says:

    how come the lava lamps that you buy at the store look gooey and you can see them better?

  33. No – you can have a clear lava lamp. 🙂

  34. Martha E Lugo says:

    do wee really need food dye?

  35. Water and oil don’t mix (called “insoluble”) and they also have different densities. If you put a cup of oil and a cup of water together, one will float on top of the other. When you heat the bottom of the mixture (usually with a light bulb), the denser liquid absorbs the heat and expands, becoming less dense…and rises. As it rises, it cools off a little and contracts, getting denser and heavier… and sinks. The trick in a lava lamp is that the oil they select has a density right around water that becomes slightly less than water when heated.

  36. Dana Carpenter says:

    How do real lava lamps that you buy in the store work? How do they keep going?