Thursday 7 September 2017

The Summer Space Project - Lava Lamps




Following on with our Summer Space project we have been learning about the Moon and also about our neighbour planet Venus.
It was really interesting learning about our neighbour planet that we wanted to explore the other planets in our solar system too.
On looking a little closer at some planets we found that a few have volcanoes on them and it was something that really interested the children.
I always find volcanoes a really alien part of our planet anyway. They are volatile, explosive and because of the different levels of structure they can be quite alien compared to the rest of the life and structure of planet earth.
Despite this there is a certain element of “they belong on earth” when actually any planet that has or had a molten core would of course have volcanoes too.
Volcanism has played a major part in shaping not only planet Earth, but other places in our universe. Though other planets show signs of volcanic eruptions, most seemed to have erupted in the distant past and are inactive now. Both Mars and Venus have volcanoes much larger than any on Earth, and they have erupted huge amounts of lava onto their surfaces in the past.
The planet Venus has a surface that is 90% basalt, indicating that volcanism played a major role in shaping its surface. The planet may have had a major global resurfacing event about 500 million years ago, from what scientists can tell from the density of impact craters on the surface. Lava flows are widespread and forms of volcanism not present on Earth occur as well. Changes in the planet's atmosphere and observations of lightning have been attributed to ongoing volcanic eruptions, although there is no confirmation of whether or not Venus is still volcanically active.
This is the cool part for children I think. The idea that lava, a hot unstable feature that is known to happen here can happen on other planets is rather cool.
We did create our own papier mache volcanoes (like any part with primary aged children should do) but the lava part was still intriguing. It was because of this that I remembered a science activity on how to make your own lava lamps and thought we could combine the two parts; volcanoes and lava and a cool activity!

Materials
Empty drinks bottle
Cooking Oil
Water
Food Colouring
Alka Seltzer
Torch/Direct Light
Method


We started by filling the empty drinks bottle a quarter full with water.


We then filled the bottle with oil.


You should leave a small space at the top for gas release.


Then we placed a few drops of food colouring into the bottle. In this case we chose blue and in the other bottle green.


Then taking one alka seltzer tablet and breaking it into small pieces and place it into the bottle and seal it with the lid.


What you will instantly see is the coloured water blobs float to the top.


To begin, the oil stays above the water because the oil is lighter than the water or, more specifically, less dense than water. The oil and water do not mix because of intermolecular polarity.
Molecular polarity basically means that water molecules are attracted to other water molecules and can loosely bond together. This is similar to magnets that are attracted to each other. Oil molecules are attracted to other oil molecules. Yet, the structures of the two molecules do not allow them to bond together.
When you add the tablet piece it sank to the bottom and started dissolving and creating a gas. As the gas bubbles rose, they took some of the coloured water with them. When the food colouring and attached water reaches the top you will find that the gas escaped and down went the water. This subsequently gives you a lava lamp effect.
It is fun to watch an instant reaction but we wanted to up this and see a greater colour movement.



Using a torch light we went into a dark room and recreated the reaction. Using the torch to highlight the movement and colour really added to the fun
This is such an easy experiment and really effective. It shows the idea of pressure, reaction, release of gas and how "lava" may move. If, like us at one point, place plenty of tablets into the bottle you will see a lava explosion like a real volcano.
Apart from this being a great science experiment and activity it fitted in with our space project and exploring lava flows with volcanoes on other planets.
We finished with the fact that Jupiter's moon Io is the most volcanically active object in the solar system because of tidal interaction with Jupiter. It is covered with volcanoes that erupt sulfur, sulfur dioxide and silicate rock, and as a result, Io is constantly being resurfaced. Its lavas are the hottest known anywhere in the solar system, with temperatures exceeding 1,800 K (1,500 ¡C) so something quite small like a bottle lava lamp is quite insignificant.
What do you think? Will you be trying this experiment at home?




2 comments:

Stephanie said...

What a brilliant experiment. Honestly had no idea you could do this kind of thing! Will be bookmarking this one for Isla when she's a bit bigger!

Care said...

A good time was clearly had by all! You're brave to venture the exploding mess indoors - we did all our volcano experiments in the back yard and I still shuddered. ;) x