The Lemonade Energy Pages are Up!

The Lemonade energy pages are up now. There are dozens of energy-related experiments and activities to try out.

The categories are divided into electrical, solar, wind (including a sub-section loaded with experiments on air pressure), kinetic/potential energy, chemical, and insulation/conductivity.

The activities include lots of interesting and diverse concepts from practical tips for building your own Rube Goldberg machine, to making endothermic and exothermic reactions, building your own solar still and using a balloon to light a florescent light tube. You can see how energy can be stored in a flywheel using your own bike and see just how heavy a sheet of newspaper can be (you may not even be able to lift it!).

I chose these particular activities because they are hands-on, lots of fun, and memorable. They also lend themselves well to group work as well as further exploration into the given topic.

This time there are a couple of experiments that we didn't pre-test that are external links (stomp rockets and elephant toothpaste). When I get to these, I will provide any feedback if needed. I usually try and pre-test everything that goes onto the site before posting. If you have tried either of these, (or any other activities on the Lemonade site for that matter!) I would appreciate your feedback so I can make the site as useful as possible for all visitors.

Side note: I did pre-test the tempera paint stenciled t-shirts that I posted here on the blog earlier, but my most recent batch ran when I washed them. I suspect I did not use a hot enough iron this time, or it could be that I accidentally used washable tempera. If you try this one out, you may want to try out a piece of test fabric first.

Power Pages

Coming soon to a website near you: the power pages full of energy-related activities and experiments.

A sample of some of the activities I'm working on:
- make your own solar still, solar cooker and solar dehydrator
- explore the effects of high and low air pressure
- make a glow in the dark geyser
- explore the role of colour and light in heat absorption
- use edible insulation to bake ice cream (this is already on the site)
- make hot ice and use household items to create heat as well as cold
- explore potential and kinetic energy with marbles and your own Rube Goldberg machine
- make your own rubber-band powered vehicle
- make your own balloon-powered vehicle

There will be lots more there too. This should be up and running by mid July.
Can't wait? Here's a chemistry quickie:

Easy Endothermic Reaction
Materials:
citric acid (sold to keep cut fruit from browning and also in craft stores for making bath bombs--The Bulk Barn sells it in containers that look like spice bottles)
water (warm but not hot)
baking soda
a spoon or stirring rod
a heavy glass container or mug
a thermometer (one with a probe-like end works best)

Method:
Dissolve a teaspoon of citric acid powder in 3-4 teaspoons of water and insert a thermometer. After a few seconds, record the temperature. Slowly add a teaspoon of baking soda a little at a time. Record the temperature, then wait 3 seconds and record it again. Repeat every 30 seconds or so for about 5 minutes. What do you notice?

Now, for the interesting twist my son discovered yesterday:
Wash off the thermometer, then leave the mixture out for an hour or so. Record the air temperature, then stir the mixture and measure it's temperature. Wait 30 seconds and measure again, then another 30 seconds and measure (and record) yet again. Now remove the thermometer and wait 30 seconds are record the air temperature again. What do you notice?

Chemical reactions that cause a drop in temperature are called endothermic. Exothermic reactions create heat.