Modelar nos permite fazer nosso próprio senso de que e porque algo está acontecendo. Modelos conceituais são representações compartilhadas e explícitas ou analogias de fenômenos e são usados pelos cientistas para ajudá-los a entender o mundo ao nosso redor. Modelos são usados em todas as áreas da ciência e oferecem versões externas de conceitos mentais. Modelos não são uma representação perfeita; eles são uma versão simplificada de um sistema que destaca certas áreas enquanto ignora outras.
It's a very hot day and Alan wants to have an ice cold glass of water. He goes over to the freezer to get some ice.
He then goes to the faucet to get some cold water.
He puts the ice inside the water.
After having a couple of sips, he leaves the glass on the window sill in the sun. He opens the window to try to cool the kitchen down.
The heat from the sun warms the water up.
When Alan comes back his glass is completely empty!
We evaporated! We're flying!
These water particles are in a solid state. They have very strong bonds between them. It does get a bit boring not being able to move around.
The water particles in the liquid state are more free than the ones in the solid state. They have more energy so they can move around, but they are still quite densely packed in.
When the ice is put in water there are two states: solid and liquid. Particles in the liquid state are close to each other, but arranged randomly. Particles in the solid state are in a regular pattern, but also closer together.
As the water gets warmer, all of the particles in the ice cube get more energy and become a liquid. They can now start to move around each other, but they are still very close.
As the water warms up, some of the particles start to evaporate, even though the temperature of the water is well below boiling point.
All the water particles have evaporated and are flying around outside!