Quimica

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QUIMICA

The apparatus is the equipment used in a chemistry laboratory. They are mostly made of glass, so the experiments can me seen easily. Usually it’s made of borosilicate glass, because the normal glass breaks with heat.
 
The four states of matter are solid, liquid, gas and plasma, all have mass, volume and density, which is found by dividing the mass by the volume, measured by 3.Solids have definite shape and a high density. It has a definite mass and volume, which doesn’t change. It’s hard to compress, but easy to make it flow. Strong forces hold the particles together. They form an orderly arrangement called a lattice. The particles vibrate always in the same position.
The shape of a liquid varies and depends on the shape of the container; it has a definite mass andvolume. It has a high density and it’s difficult to compress, it’s easy to make it flow. There forces that hold together the particles are weaker then by the solids. They vibrate faster and they can change position by sliding over each other.
The shape and volume of a gas varies and it’s easy to compress and make it flow. The forces of attraction between the particles are very small and they can travelin all directions. When they ht each other, they bounce and change direction.
 
Solids and liquids can generate pressure. A gas has not a surface like a solid or a liquid, but it pushes on any surface with which it makes contact. If a gas is heated, the pressure increases, but if it’s cooled, the pressure falls. When a gas is kept in a small container, the particles bounce off the containerwalls more frequently and the pressure rises.
 
The state of matter of a substance can be changes by changing the pressure acting on it.
 
There is less pressure in other planets than in earth.
 
Melting and freezing:
Melting is when a solid is heated, making its particles vibrate faster (more energy) and change shape. The temperature in which this happens is called melting point.
Freezing iswhen a liquid is cooled enough, making its particles vibrate slower (loose energy) and forms a shape (turn into a solid). The temperature in which this happens is called freezing point. Both, melting and freezing points are the same temperature.
Evaporating and Boiling:
Evaporation is when a liquid turns into a gas over a range of temperatures. This happens because the particles in the liquidhave different amounts of energy. The higher the temperature, the faster the evaporation.

Boiling is when at a certain temperature the gas forms inside the liquid and makes bubbles (all the particles move faster because they have more energy), which rise to the surface and burst into air. The temperature in which this happens is called boiling point. If the liquid is heated more strongly, thetemperature doesn’t rise but it boils more quickly. Boil at low pressure accelerate the process, allowing the evaporation take place more quickly. Boil at high pressure lets the gas escape, because the pressure pushes the lid.
Condensation:
It’s when a gas is cooled down and turns into a liquid, this happens because the particles in a gas have a large amount of energy, and when they are cooleddown, they loose it, which makes them move slower.
Sublimation:
It’s when a solid turns directly into a gas without changing first into a liquid, or from gas directly too solid. (z.B. Dry ice). This happens when the energy the particles receive makes them separate and form a gas without forming a liquid first.
 
When a substance changes state, its mass doesn’t change.
 
Diffusion is a processin which one substance spreads out through another.
 
Water turns into vapour (gas) by evaporation, then the vapour condensates and forms millions of little water droplets to make the clouds. The temperature of the clouds is so low that the droplets freeze and form snowflakes. When they fall (precipitation) they melt and form rain. The plants roots take up the water that passes through the...
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