Fun with Bottled Lava Activity

We have recently been on a volcano kick lately…the recent rainy day marathon has had my kids stir crazy and eager to find ways to make things go ‘boom’ or race quickly across the house. So, they have been playing chase, pushing race cars across the house, blowing up balloons and then volcanoes came into mind. Volcanoes are the perfect thing to go ‘kaboom!’ and bring some action to these confined kiddos. After brainstorming ways we could conduct our very own volcano activities, we narrowed it down: constructing a volcano and making bottled lava. Fun times ahead!

The first activity we went for was the bottled lava. Lava is really cool! Actually, it is pretty hot….Lava is molten (melted) rock that is expelled from a volcano. Can you imagine how hot that has to be? Obviously we are not going to involve any real lava in this activity, but the simulation is pretty close to that of lava. Another great educational tidbit that goes along with this activity is the idea of oil and water. Oil and water do not mix due to their physical properties. They will always remain separated in a mixed solution. The oil is also less dense, so it will float to the top. Whereas the water is more dense and will sink to the bottom. This bottled lava activity demonstrates that relationship! It is what forms the ‘lava’ in the bottle.

Ready for some lava fun?! Let’s get started…

Items Needed:

1 16oz water bottle, empty, with cap
Vegetable oil (enough to fill the water bottle 3/4 full)
Alka Seltzer, 1 tablet
Food Coloring
Water

Steps:

1) Take the empty water bottle and fill it 3/4 full with vegetable oil, about to the top of the water bottle label
2) Add water to the bottle until it reaches right below the mouth of the bottle (cap screw).
3) Add 4-6 drops of food coloring-it will only mix with the water component
4) Take the Alka Seltzer tablet and break it into 8 pieces (pieces don’t all have to be the same size)
5) Now for the fun! One at a time, drop a piece of the Alka Seltzer tablet into the water bottle. Once it sinks and reaches the water aka lava, the bubbles will begin to form. When the bubbles slow down, another piece of the tablet can be dropped in. This will be repeated until the very last piece of Alka Seltzer is added. Once the last piece is added, wait for the bubbles to completely stop before screwing the cap on.
6) Now that the cap is screwed on tightly, the bottle can be placed on it’s side and rocked back and forth. The water (lava) will rock side to side. My kids of course got a little excited and shook their bottles up. If this happens, it will just take a few minutes for the water to settle back down to the bottom and the oil to settle at the top. I am mentioning this because my kids freaked out thinking they destroyed their bottled lava!

If you have very intuitive kids, they may ask why is the water bubbling when you add the tablet pieces. When Alka Seltzer is dropped into water, it reacts with the components of water to form both water and carbon dioxide gas. This gas forms the bubbles in the water (lava) portion of the mixture. The bubbles are seen very clearly as they float up through the oil layer in the bottle.

I hope you all enjoy this activity as much as we did! I have included a fun volcano coloring sheet below as well as a picture of molten lava..it really is pretty 🙂

Volcano Coloring Sheet
Molten Lava Image

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