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    | • | Charles, a hot
    air balloonist, (1800’s) 
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    |  | investigated how
    V and T (temperature in 
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    |  | K) were related. 
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    | • | He found that as
    the temperature of the gas 
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    |  | increased, the
    volume occupied by the gas 
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    |  | also increased as
    long as the pressure and 
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    |  | amt of the gas
    were held constant. 
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