Lava Lamps : The Ultimate Kids Science Experiment

Lava Lamps have to be one of the funnest science experiments we've ever done. Seriously, if you want to know how to make science fun for kids and encourage their sense of wonder you can't look much further than this.

Experiment - check, there are fluids and solids involved and  scientific gear required. Hands on - check, lots of pouring, mixing, shaking. Relevant - check, who doesn't think a funky lamp like this would be a great addition to any kid's room? Can be supported by interesting documentaries - check, and books - check.

So on to the details.  

Bubbling Beauty - Lava Lamp

Lava Lamps

 

Materials

• Clear glass or plastic bottle
• Vegetable Oil (liquid)
• Water (liquid)
• Food Colouring (liquid)
• Alka Seltzer tablets(solid)

 

What we did

• First we poured the vegetable oil into a tall glass jar.

• Then we used a dropper to drip water into the oil This meant the kids could see how the water didn't mix with the oil but sank through it to pool at the bottom. I prompted their observations by asking them to watch what happened and describe it to me. We then talked about how this was because the water was denser than the oil. If you look closely at the picture below you can see the water droplets beginning to cluster at the bottom of the jar.

Dripping water into the oil

• We did the same with the food colouring and again observed how it passed through the oil and then mixed with the water.

Passing through the oil

Mixing with the water

•  We took half an alka-seltzer tablet and dropped it into the jar and watched what happened.

Watching the Reaction

• We asked ourselves what else we could experiment with? What would happen if we put the lid on or dropped in a whole alka seltzer tablet? We also added some blue food colouring to the red to see what that would do. And then we got out our biggest torch and put it underneath the bottle.

Watching to see what happens!

Lovely Shades of Purple

• And just for good measure, we made some more! Three children often means three experiments. We began this together but luckily I had just enough oil and alka seltzer for them to do it again in smaller jars. This time they each worked by themselves and tried out some things differently to see what happened. Shaking happened, tipping upside down happened, adding differing quantities than the first time happened. And a lot of smiling and delight in the magic bubbles each and every time.

Lotta (5)

Noah (8)

Maya (11)

Best for...

Our sense of wonder. If you had to ask me what was the single thing that made this the ultimate kids science experiment for me so far, it would have to be the sheer delight on my kid's faces every time those bubbles appeared. With such simple and easily obtainable ingredients we did something really special.  There is something amazing about Lava Lamps. They reveal the beauty and wonder of chemical reactions between liquids, solids and gases in a very peaceful and stunning way. 

Watching the Lava Bubble

 
In conclusion, we had great fun with this experiment. It allowed us to continue exploring states of matter (check out our other experiments here) as well as the concept of density. As usual we wrote the experiment up on paper (more about how that works for kids of different ages next week) and talked about the science. We also learned about how real lava lamps are made by watching this documentary as well as reading about chemical reactions in our science books.