|  |  |  |  |  |  |  |  | 
   
    | • | By changing the
    temperature (and pressure) 
 | 
   
    |  | 
   
    |  | all matter can
    exist as a solid, as a liquid 
 |  | 
   
    |  | 
   
    |  | and as a gas. 
 |  | 
   
    |  | 
   
    | • | There are forces
    of attraction (which we 
 |  | 
   
    |  | 
   
    |  | learn about
    later) btn cmpds that determine 
 |  | 
   
    |  | 
   
    |  | what physical
    state (gas, liquid, solid) we 
 |  | 
   
    |  | 
   
    |  | find the cmpd in
    at a given temperature. 
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