Combined Gas Law

The Combined Gas Law is used to deal with changes in all of the variables: moles, temperature, pressure, and volume. The formula we use to calculate this is:

Source

Example: A bubble rises from the bottom of a lake when temperature and pressure are 8C and 6.4 atm. The bubble reaches the surface where it is 25C and 1atm. What's the final volume of the bubble if the initial was 2.1mL?

P1=6.4atm   V1=2.1mL   T1=8+273.15=281.15C    P2=1.00atm   V2=?   T2=25+273.15=298.15C

6.4(2.1)298.15=1(V2)281.15   =    14mL

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