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Chemistry - the states of matter

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Physical Chemistry


This page relates to the physical factors affecting chemical processes..

States of matter

Matter exists mainly in three states gas, liquid and solid.  A material such as water can exist as a gas (steam) a liquid (water) or a solid (ice).   Its state results from its condition of temperature and pressure.

A gas has no bounding surface it fills all of the space it occupies.   Its density is very much related to the quantity of matter the temperature and the pressure.

A liquid has no shape. It takes the shape of the vessel it occupies.   It does however have a surface which limits the volume it occupies.   It is normally has a greater density than a gas. Its volume and related density is affected to some extent by temperature and to a lesser effect by pressure. Liquids are often assumed to be incompressible

A solid has a fixed shape and its volume changes by only a relative small amount on changes of pressure and temperature.

In normal conditions a solid can be converted to a liquid if its temperature is raised to its melting point temperature and a liquid can be converted to a gas if its temperature is raised to its evaporation tempature which is related to the local pressure..

Ideal Gas Real Gas Liquid Solid

Relevant sites..
  1. Sheffield University Periodic Table this Site includes extensive Chemical information
  2. AP Chemistry -Study Cards... A set of chemistry study cards- Ideal look up revision aids
  3. Wikipedia Physical Chemistry... Lots of useful reference information- users can contribute
  4. Physical Chemistry by P.Atkins & J.D Paula... An Online reference book- Excellent reference material
  5. Understanding Physical Chemistry...Nice simple Presentation and break down into subject elements