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Science progress affects our daily life and "to know" means you are going to chose right, because it allows you to form your own opinion on scientific everyday issues. On the other hand, having an elegant and harmonious vision of the world where we live in leads to a feeling of intellectual satisfaction.
We believe this kind of scientific day to day knowledge should be encouraged from an early age, and that's why this project was born: science, culture, knowledge, crafts for your restless mind.

Tuesday, November 8, 2011

Fire proof ballons


Balloons are fun, in fact they are the funniest thing in the world for a young child. You can blow them up, you can lose it, you can make them fly with He, they can be bend to form animals... or they can be part of a magical moment.
Today we will show you another funny thing you can do with balloons.  It's very simple but requires the presence of an adult, from beginning to end of the test

We will need:
  • 2 balloons,
  • 1 candle,
  • water, cold, or a piece of ice,
  • funnel,
  • Matches or a lighter.
How to:
  1. With the help of the funnel put a little water in one of the two balloons;
  2. Fill the two balloons, so that they are the same size;
  3. Place the candle inside the sink, or another place you can wet without much trouble;
  4. Light the candle, the adult should do this;
  5. Touch the flame with the balloon that doesn’t have water. What happens?
  6. Now try the other one, flip the balloon around slowly. What happens?

The first balloon burst almost immediately, the second balloon, which contain water, takes longer to break (depending on the amount of water you put in there it may not even burst, it also depends on the rubber quality).

Why?

Both the first balloon and the second (with water) heat.
On the first one the flame heats the balloon, the rubber loses the properties that allow it to withstand the pressure of air that is inside, and consequently bursts.
The second balloon, the presence of water changes everything. In fact when the balloon is placed in the flame its not the balloon that gets hotter but the system water / balloon. The flame heats the rubber in contact with water, and the heat is transferred to the liquid, thereby allowing the rubber of the balloon to cool, and maintain properties longer.

Water absorbs heat very well. We need a huge amount of heat to change the water temperature. Notice the time it takes to heat water in a kettle and compare it with the time it takes to heat the kettle itself (do not touch the kettle!)
On the other hand, the cooling process of water releases a tremendous amount of heat, this contributes to the fact that the areas near oceans - or other bodies of water - are not so cold in winter as areas further inland.

These is a demonstration, turn this in an experiment by varying the amount of water in the balloon, or the water / air system, the time it takes to blow the balloon is influenced by these factors?
Record your results in a notebook, then try to make a graph that reflects the results, there is a direct relationship?

I leave you this video,



Et voilá!
The heat transfer at our fingertips

Enjoy!

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