The Gases and Gas Laws Behavior of Gases  Volume, Temperature, and Pressure  Boyle’s Law  Charles’ Law

SPS5b  Students will compare and contrast the phases of matter as they relate to atomic and molecular motion.  B. Relate temperature pressure and volume of gases to the behavior of gases.

GASES The behavior of a gas is affected by changes in temperature, pressure, and volume. The relationship of these 3 variables are explained in the gas laws.

Pressure,Volume,Temperature  Pressure is force exerted over a certain area. Measured in atm, kPa, mm Hg.  Volume is capacity. Measured in mL or cubic cm  Temperature is measured in degrees F, C, or K.

Gas Law Ruler  Find the constant (P, T, or V). Hold the ruler at that point between thumb and forefinger. Either move the ruler up or down depending on what the problem says and see what happens to the third constant! Let’s try it! P T V

Using the GAS LAW Ruler  Mary Jane took her helium balloon to the hockey game. The volume of a balloon is constant. But when she went from the hot outdoors to the cold indoors, she found her balloon ________ in pressure!

Real Life Gas Laws  What does this tell us about what might happen to: Car tires when the weather changes? Aerosol cans left in cars in August? Power lines in the winter, If electricians failed to string them with some sag in the summer?

Boyle’s Law  When the volume of a gas decreases, its pressure __________ (at constant temp). P V INVERSE

V T Charles’ Law  When the temperature of a gas increases, its volume __________ (at constant pressure). DIRECT

Absolute Zero  Absolute Zero - Temp at which...  the volume of a gas would equal zero.  all particle motion would _________. -273°C or 0 K