Chapter 12.2Gas Laws

Charles’s Law

ReviewWhat is the distance between particles

called?

What is Boyle’s Law?

If the pressure doubles, what happens to volume?

Kinetic-Molecular TheoryAs particles heat up, they start to move

around faster.

This causes them to hit the walls of their container with more force.

Repeated strong collisions cause the volume of the container to expand (or break)

Kinetic-Molecular TheoryIf the temperature decreases, the volume

decreases.

Charles’s LawLooks at the direct relationship between

temperature and volume.

= k

Or

=

ExampleA balloon is inflated to 665 mL volume at 27oC. It is immersed in a dry – ice bath at -78.5oC.

What is its volume, assuming the pressure remains constant?

Pull information out that is givenT1 = 27oC

V1 = 665 mL

T2 = -78.5oC

V2 = ?

Equation: =

RememberWhen dealing with the gas laws,

TEMPERATURE HAS TO BE IN KELVIN

To convert Celsius to kelvins simply add 273oC + 273 = Kelvin

T1 = 27oC + 273 = 300 K

T2 = -78.5oC + 273 = 194.5 K

T1 = 300K

V1 = 665 mL

T2 = 194.5 K

V2 = ?

=

=

V2 = (665)(194.5)/300

V2 = 431 mL