Mountain Quest 3: Volcanoes

How to Make a Volcano

Instructions adapted from Science Fun.


  • 10 ml (about 2 tsp) dish soap
  • 100 ml (about 1/2 cup) cold water
  • 400 ml (about 1 3/4 cup) white vinegar
  • Food coloring
  • Baking soda slurry (fill a cup about ½ with baking soda, then fill the rest of the way with water)
  • Container (such as an empty 2 liter soda bottle or any hollow plastic container, Play-Doh or clay shaped into a hollow cone, or Plaster of Paris or papier-mache hollow cone)


NOTE: This should be done outside due to the mess.

  1. Combine the vinegar, water, dish soap and 2 drops of food coloring into your container.
  2. Use a spoon to mix the baking soda slurry until it is all a liquid.
  3. Pour the baking soda slurry into the container quickly and step back!

How It Works

A chemical reaction between vinegar and baking soda creates a gas called carbon dioxide. Carbon dioxide is the same type of gas used to make the carbonation in sodas. What happens if you shake up a soda? The gas gets very excited and tries to spread out. There is not enough room in the bottle for the gas to spread out so it leaves through the opening very quickly, causing an eruption!

How does a volcano really erupt?

Deep within the Earth it is so hot that some rocks slowly melt and become a thick flowing substance called magma. Since it is lighter than the solid rock around it, magma rises and collects in magma chambers. Eventually, some of the magma pushes through vents and fissures to the Earth’s surface. Magma that has erupted is called lava.

Some volcanic eruptions are explosive and others are not. If magma is thin and runny, gases can escape easily from it. When this type of magma erupts, it flows out of the volcano. If magma is thick and sticky, gases cannot escape easily. Pressure builds up until the gases escape violently and explode. In this type of eruption, the magma blasts into the air and breaks apart into pieces called tephra. Tephra can range in size from tiny particles of ash to house-size boulders.
(Source: United States Geological Survey

Eruption. Clubs of smoke and ash in the atmosphere.

Lava flow on the Big Island, Hawaii

Mouth of the volcano with magma. Molten magma in the muzzle.

volcano fun at home

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