Evaporation+and+Condensation

= ** The Conversion of Liquids to Gases and Gases to Liquids **     = = =  Well first you have to know that a liquid is a state of matter in which the molecules are close together but not in the same arrangement as in the molecules of a solid. Water is an example of a liquid. Your blood is a liquid too. A gas is a state of matter too in which its molecules are much more spaced out than a liquid's or a solid's and a its' molecules move much more rapidly. The atmosphere is a big layer of gas that surrounds the Earth. A liquid changes from a liquid to a gas by evaporation and a gas changes from a gas to a liquid through condensation.
 * The question: "How does a liquid change from a liquid to a gas and how does a gas change from a gas to a liquid?" **



  **Evaporation **    Evaporation usually happens when liquids are warm but it can also happen when they are cold. Evaporation has to do with the energy in individual molecules and it happens when molecules or atoms escape from the liquid and turn into vapor, which is the same thing as gas. Not all of the molecules have the same amount of energy. Molecules that have a lot of energy usually build up enough power to turn into a gas and when that level is reached they can evaporate the liquid. Two factors that affect evaporation are temperature and gas pressure. Evaporation increases with a decrease in the pressure around the liquid and the opposite happens with an increase in pressure. Molecules usually move from areas of high pressure to areas of low pressure. What basically happens is that the molecules are sucked into the are surrounding the liquid and the pressure is evened out. The rate of evaporation will slow down after the vapor pressure of that area increases to a specific level. When the temperature rises that rate of evaporation does too. When it gets warmer the molecules start to move about more rapidly. We have to remember that evaporation can take place at any temperature but rising it can increase the odds of molecules escaping the liquid.

** Condensation ** 

Condensation is the process through which a gas turns into a liquid. What happens during condensation is that the atoms loose enough energy to become a gas. What causes this is the decrease of the temperature around the gas. When the temperature drops the atom's energy is sucked out of the atoms. When the temperature of the condensation point is reached the gas becomes a liquid. An example of this would be the steam of a boiling pot of water. As soon as the steam hit the wall it would become water because the wall would be so cool.

Sources Pictures
 * CHEM4KIDS. Andrew Rader Studios. 14 Feb. 2009 http://www.chem4kids.com/files/matter_changes.html
 * CHEM4KIDS. Andrew Rader Studios. 14 Feb. 2009 http://www.chem4kids.com/files/matter_evap.html
 * CHEM4KIDS. Andrew Rader Studios. 14 Feb. 2009 http://www.chem4kids.com/files/matter_liquid.html
 * CHEM4KIDS. Andrew Rader Studios. 14 Feb. 2009 http://www.chem4kids.com/files/matter_gas.html
 * http://www.harris-interiors.co.uk/liquid%20blue.jpg
 * http://www.envirohub.net/images/what-are-greenhouse-gases%20pic.jpg
 * http://www.tapintoquality.com/facts/glossary/evaporation.jpg
 * http://www.chem4kids.com/files/matter_evap.html