13 Sept 2011

Form 1: Contraction and Expansion of Matter

Contraction and expansion of matter occurs everyday around us. We don't observe it enough, but it is happening.

1. Changes in states of matter (freezing, melting, condensation, evaporation, sublimation, boiling) all involves heat transfer.
2. Heat transfer will cause matter to contract or expand. When matter gains heat, it expands. When matter loses heat, it contracts.
3. Matter expands because when it gains heat, its kinetic energy will increase. When kinetic energy increase, it moves faster. When it moves faster, it will move further apart and take up more space.

As shown in class today, these are the videos:



To recap what was shown in the second video, liquid nitrogen is verrrrrrrry cold. Its boiling point is very low, hence it is boiling at room temperature (the temperature of your surrounding in a room). Liquids DOES NOT have to be hot to boil, it will boil when it has enough energy to break the forces of attraction and become a gas (remember the puzzle we did).

If you have any questions, please post a comment.

Cheers.

1 comment:

Anonymous said...

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