Charles Law

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PowerPoint Handouts for Volume and Temperature Relationship

The relationship between temperature and volume

The mathematical statement isthat the V / T =aconstant. For two setsof conditionsthe following isa mathematical statement of Charles'sLaw: JacquesCharlesinvestigated the relationship between the Volume of a gasand howit changeswith temperature.

Charles's Law states that the volume of a given amount of dry ideal gas is directly proportional to the Kelvin Temperature provided the amount of gas and thepressure remain fixed.

V1/ T1=V2 / T2

If the volume of a container isincreased, the

temperature increases. If the volume of a container isdecreased, the

temperature decreases.

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Before going to some sample problems, let'sbe very clear: EVERY TEMPERATURE USED IN A CALCULATION MUST BE IN KELVINS, NOT DEGREESCELSIUS. DON'T YOU DARE USE CELSIUSIN A NUMERICAL CALCULATION. USE KELVIN EVERY TIME.

A sampleof gasoccupies3.5 L at 300 K. What volumewill it occupy at 200K? Solution: V1/ T1=V2 / T2 given: V1=3.5 L, T1=300K V2=?,, T2=200K

3.5L/ 300K =V2/ 200K V2 =(3.5L/ 300K) x 200K =2.3 L

What isthe approximate temperature for absolutezero in degreesCelsiusand kelvin? Absolute zero -273 degreesCelsiusor 0 Kelvin

If 1L balloon isheated from 22 °C to 100°C. What will itsnewvolumebe? Solution: V1=1L

Example:

V2 =(V1/ T1) x T2 (1L/ 295K) x 373K V2 = 1.26L

100 °C =373 -15 °C =258

Calculate the missing temperatures: DegreesCelsius(° °C ):

Kelvin (K):

0

273 ____

115

388 ____

-30

243 ____

1 30 ____

403

-30 ____

243

T1=22 °C =295K T2=100°C =373K