During our reading session today, the boys came across an experiment called, Electric Bubble-Maker.
This discovery signalled the end of quiet reading and the beginning of a science experiment as everyone went scattering for the required materials.
By the way, in case you're wondering, the Electric Bubble-Maker experiment was found in a book by Chris Oxlade entitled "Super Science. Matter and Materials Experiments". This is a great book with 10 hands-on experiments for curious scientists of the kid-sized variety!
The Electric Bubble-Maker experiment worked really well and was easy to set up and do. While the bubbles were miniscule, the boys really enjoyed doing this activity.
Materials Required for the Electric Bubble-Maker Experiment
- thick cardboard
- 2 lead pencils - the same length
- a glass half-full of water
- 9 volt battery
How to Make an Electric Bubble-Maker
1. Sharpen both ends of each pencil.
2. Cut the cardboard so that it overhangs the edge of the glass by 2cms on each side.
3. Push the pencils through the cardboard so there is approximately 1 centimetre between the pencils.
4. Place the pencils in the water so that their ends are level. Be careful not to let the pencils touch the bottom or sides of the glass.
5. Hold the battery upside down and connect to the exposed pencil leads at the top of the pencils.
6. Observe the leads and look for small bubbles forming around the pencil leads in the liquid.
How Does the Electric Bubble-Maker Work?
Water is made up of two chemical elements - oxygen and hydrogen. Oxygen bubbles form on the pencil lead connected to the positive battery terminal while hydrogen bubbles form on the pencil lead connected to the negative battery terminal.
Use the Electric Bubble-Maker to Create Smelly Bubbles!
Remove the pencils and stir salt into the water.
Repeat the experiment using salty water and then sniff the air within the jar. This time you'll smell chlorine just like the water in a swimming pool.
NOTE: Be careful not to add too much salt. We found this out the hard way. When one of our enthusiastic scientists added a 'truck load' of salt, the chlorine smell was extremely strong!!!
Why Does the Electric Bubble-Maker Make Swimming-Pool Smelling Bubbles?
The pencil lead connected to the positive terminal creates chlorine.
When you remove the pencils, carefully smell the ends of the two pencils. One of the pencils will smell of chlorine while the other won't.
Creating an Electric Bubble-Maker certainly appealed to the scientists in our house. What do your scientists like to explore? We'd love to hear about your adventures with science experiments. Feel free to leave a comment on this post or on our facebook page.
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