Ignore this it wont let me delete this page :D

Similar to liquids gas changes shape and fills the volume of the space around it. The particles expand until there is something preventing them from continuing. 

volume:

- the amount of space a substance takes up ( usually measured in liters or V) 

temperature: 

-  physical quantity that expresses hot and cold (measured in kelvins I)

pressure: 

- the amount of force put on something (measured in atmospheres P)

- statement -  it only exist  in ideal conditions

Avogadro’s Principle:

    ~~~~~~|~~~~~~~~~~ = (x) L

                   1 mol