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"This is actually very similar to what happens when popcorn pops or when you try to microwave a marshmallow. Those air bubbles in the soap (or the popcorn kernels or the marshmallow) contain water. Water is also caught up in the matrix of the soap itself. The expanding effect is caused when the water is heated by the microwave. The water vaporizes, forming bubbles, and the heat causes trapped air to expand. Likewise, the heat causes the soap itself to soften and become pliable. This effect is actually a demonstration of Charles' Law. Charles' Law states that as the temperature of a gas increases, so does its volume. When the soap is heated, the molecules of air in the soap move quickly, causing them to move far away from each other. This causes the soap to puff up and expand to an enormous size. Other brands of soap without whipped air tend to heat up and melt in the microwave."

This is a science video about Conduction of Heat for Grade 6-7 students. It demonstrates the transfer of heat with an activity and explains the conditions required for conduction of heat.

"Most of us have a microwave oven in our kitchen. They make heating up leftovers and the dreaded readymeal much faster than a conventional oven. In this Naked Science Scrapbook, we find out how the microwave oven produce the microwaves, and how they actually cook the food, plus how popcorn played a key role in the invention of the microwave oven"

"Astronomers have a mind-blowing new theory: that there are 17 billion Earth-sized planets in our galaxy. They don't yet know how many of these worlds are in habitable zones, but the implications of this discovery are amazing. So much that some claim the "quest for a twin Earth is heating up." Simply put: If there are 17 billion Earth-sized worlds in our galaxy, it's clear that the Universe is bubbling with life."

Looking at water and ice with infrared light helps us understand how light and heat are related.

A Steve Spangler video experiment that might be good for teaching students about the Law of Conservation of Energy. Involves making a solar powered oven to convert light energy to heat energy to cook S'mores.

Huw James took a trek up Mount Etna and decided to show us what actually happens when a volcano erupts!

With a little bit of help from Dr Suze Kundu and using a simple demonstration heating a glass beaker of wax, stone, sand and water we can see what happens when a volcano erupts.

We can actually tell a lot about a volcano looking at the lava that comes out. If the lava is quite dense and thick we know it contains a lot of the compound silica. If it is less dense it has less silica and spreads out a lot more.

Thick lava will generally erupt from one vent and follow one flow down the side of the volcano. Thinner lava, lava that is less dense, generally erupts from the surrounding magma chambers and flows in many different channels.

"There are just some things that are synonymous with "summertime snacks," and we can't think of a summer snack we enjoy quite as much as s'mores. But what would you do if you weren't allowed to have a fire or just didn't have the tools necessary for a fire? We came up with a pretty neat way to harness the heat and energy of the sun to create a solar powered cooker that makes a delicious batch of s'mores without a fire!"

"Steve Spangler discovers the microwave oven is not just for warming leftovers. Grab a bar of fresh Ivory soap and gather your friends around the microwave oven. Sure, you could do it at your home, but save this great trick for the break room or the staff cafeteria. In under two minutes, you'll have the best soap soufflé you've ever seen."