|  |  |  |  |  |  |  |  |  |  |  | 
   
    | • | 4. At a given
    time the gas molecules have 
 |  | 
   
    |  | 
   
    |  | different speeds
    and different kinetic 
 |  | 
   
    |  | 
   
    |  | energies but the
    average kinetic energy of 
 |  | 
   
    |  | 
   
    |  | all the molecules
    of the gas is directly 
 |  | 
   
    |  | 
   
    |  | proportional to
    the Kelvin temperature(T). 
 | 
   
    |  | 
   
    | • | KEaverage  µ T or 
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    |  |  | 
   
    |  | 
   
    | • | KEaverage
    = cT where c is a constant 
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    |  |  | 
   
    |  | 
   
    | • | Note that as 
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    |  | 
   
    | • | Gases that obey
    these assumptions are 
 |  | 
   
    |  | 
   
    |  | known as 
 |  |