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Many people go on camping trips every day, all year long.
On these trips they take food.
Most of them put it in a cooler with ice packs.
But after a few hours the ice packs melt and the food begins to spoil.
Not anymore!
We have the FreezeStick!
The FreezeStick is a plastic tube.
It is divided into two sections by a piece of glass.
Each section contains a different chemical.
When the ice packs in the cooler melt, you bend the FreezeStick to break the glass,
shake it, and put it in the cooler. The FreezeStick absorbs the heat
and causes the ice packs to freeze. This is called an endothermic reaction.
Here in the 7 World Wonders' lab in Yerucham, Israel
Dr. Deutsch will explain how the endothermic reaction works in the FreezeStick.
Dr. Deutsch...
An endothermic reaction is a chemical reaction
that absorbs energy from the environment. And now we will show an example
of an endothermic reaction. In this particular example, we took two chemicals
and mix them together in a beaker.
Then we give it activation energy by shaking it.
Look, the temperature is dropping - it's amazing!