Question: hello my name is Messi123 I love science and I think this site is a very good idea. Do you know how to make a volcano ?

Rebecca Williams answered on 16 Jun 2014:

Hello!
Oliver has already told you how to make the most common way you yourself can make a volcano. You could build yourself a volcano shape out of papier-mâché and try erupting your vinegar and baking soda lava out of it!

Volcanic eruptions happen because of the gas in magma (lava underground). Those gases make bubbles and when you have too many bubbles, it makes a froth and comes whooshing out. You can make this happen by doing the Diet Coke and Mentos eruption (instructions here: http://www.sciencekids.co.nz/experiments/dietcokementos.html) but please ask your teachers or parents first!

As volcanologists, one of the ways we try and understand how volcanoes work is by trying to make one in the lab. Sadly though, we can’t make a volcano in the lab that is able to behave like a real one would. Real volcanoes are too complicated. Instead, we try and make them do just one or two things like real volcanoes.

For my students I do two different volcano practicals. The first, the bin volcano, tries to show how gas that makes volcanic eruptions happen. What I do is fill a big bin with water. Then I put some liquid nitrogen in a coke bottle. Liquid nitrogen turns from a liquid to a gas very very quickly in normal air temperatures. So, when I put the bottle of liquid nitrogen into the water, the liquid turns to gas and bursts through the bottle, erupting the water out of the bin (there is a picture on my profile). This is the same as when the gases come out of the magma and erupts magma out of a volcano. You can watch videos of me doing this experiment here: https://www.youtube.com/playlist?list=PLhJA5xYrlKbKY5B0TEbYWBZOYnd573Pip We’ve also put coloured balls in the water so we can work out how big our eruption is and see how volcanoes make rocks fly through the air.

We can also make our own lava. I use a Thermite reaction (ask your chemistry teacher!) to make lava. You can watch that video here: https://www.youtube.com/playlist?list=PLhJA5xYrlKbKQ4lM02k0RZCzDyKYKVt0D But some colleagues of mine over at Syracuse University in America make much bigger lava flows, watch here: https://www.youtube.com/watch?v=U5NjVNM5Iog

This week, colleagues at my old university in Buffalo are making explosive volcanoes by using dynamite. They are trying to understand how big volcanic explosions underground work. Take a look at some of their pictures here: http://blogs.agu.org/magmacumlaude/2013/05/23/starting-off-the-summer-with-a-bang-more-man-made-maars/ I wish I could go along to watch!