Homemade Science Experiments: Lava in a Jar

If it were up to Austin & Addie, we would daily create some sort of homemade science experiments.  They love hands on learning and creating something, seeing cause and effect.  When I was in school, I had a sixth grade science teacher in Heber, Utah that was awesome!  He was all about hands on learning and I so looked forward to his class.  Each and everyday we learned through hands on science.  It made learning exciting, the see it before your own eyes rather than learn just through a book.


This year we are determined to take hands on learning to a new level.  Miss B is right along side us each and every day with her little inquisitive mind.  I hope that it will harbor a love of learning, create a spark in their imaginations and lasting impressions on their memory.

For today, we considered several from a list of homemade science experiments and settled on Lava in a Jar.  We recently studied about the volcanoes and the eruption in Pompeii so it was fresh on their minds.  Austin has always been interested in volcanoes and would love to see one, someday.

Without further ado, this one is so simple and you will likely have everything you need in your kitchen and medicine cabinet.  For your little ones, I would suggest a little more hands on help.


Lava in a Jar

Supplies Needed:

  • A clear plastic bottle or jar
  • A bottle of vegetable oil
  • Water
  • Alka Seltzer
  • Food coloring

Homemade Science Experiments Lava in a Bottle in Process

We used mini sized water bottles because it was what we had on hand but you can use a larger bottle or glass jar.  Fill it about 1/4 way full with water.  Then add your vegetables oil to fill the jar, leaving about 1 1/2-2″ space on the top.  As you know, the oil and water don’t mix, but separate into two layers with the water on the bottom.

Once the liquids fully separate, now is the time to add 6 – 8 drops of food coloring.


Then add 1/2 of an Alka Seltzer tablet and watch the action. As the bubbles start to die down, ass another half of a tablet to watch the action again.



That was fun, so whats the science behind it?

Explanation for younger children: The molecules in water are a polar molecule and are attracted to other polar molecules, think Mickey Mouse shaped.  Oil molecules are non-polar molecules.  Because each type is attracted or wants to hang out with only those that are like themselves, they just don’t mix.

Once they separate with their own types, the oil floats to the top because it has a lower density.  The density of an object goes back to which has more mass

Density is a measurement of how solid something is. Specifically we are talking about the mass of a substance. If you have two objects of the exact same size (volume), the more dense object will weigh more than the less dense object.  In this case, the oil is less dense than water and floats to the top.

Stay tuned as we are working on creating fun videos for our homemade science experiments!

Homemade Science Experiments : Lava in a Jar - Science in the Kitchen

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