Volume and Density

• Ice on water, displaying the properties of volume.duck with red paws on the ice of the pond looking in the camera image by Daria Miroshnikova from Fotolia.com
  
  According to Word IQ," Volume is a quantification of how much space an object occupies." When matter changes from a gas to a liquid its density increases while its volume decreases. As the volume of a substance decreases during matter phase transition its density generally increases. An exception to this rule is the transition of water to ice, in which the density of ice is actually less than water. This is what causes ice to float.
  
  

Temperature

• The process of temperature risingtemperature image by Edsweb from Fotolia.com
  
  A decrease in temperature causes matter to change from a gas to a liquid. Temperature has such a direct influence over the state of matter due to its ability to change the speed of the molecules which make up a substance by giving or taking energy. As the temperature decreases when matter is in its gas forms, the molecules no longer have enough energy to resist molecular attraction, resulting in the formation of a liquid.
  
  

Pressure

• A hot air balloon's operation relies on pressure.balloon ride image by redrex from Fotolia.com
  
  As the energy within matter decreases the pressure it can exert decreases as well. Matter as a gas displays energy as molecular collisions. An example of this is a balloon. If you were to lower the temperature of the gas in the balloon until it turned into a liquid it would then deflate, due to the decreased pressure. When a gas turns into a liquid the equivalent mass will create a much lower pressure.