1. The Ideal Gas Law

2. Amedeo Avogadro (Lawyer & Physics Professor)
Observed different gas samples and found that EQUAL VOLUMES OF ALL GASES AT THE SAME TEMPERATURE AND PRESSURE HAVE THE SAME NUMBER OF MOLECULES
Is this a law or a theory?

3. Temperature MUST be in KELVIN!

4. Why is it called the “Ideal” gas law?
This law falls under the larger theory called the Kinetic Molecular Theory
This theory is used to describe how gases behave under different conditions.
The word “ideal” means that we make assumptions about the gas (Ex: There is no intermolecular forces).
HOWEVER, MOST “real” gases do not behave ideally, except under very extreme conditions.
While 100% ideal gas behavior is rare, the law is used to calculate conditions that do affect gas properties.

5. Which gas constant do you use, and why?
Select the R-value that corresponds to the unit of pressure that you are dealing with in a given problem
Ex: How many moles of gas are contained in a sample that exerts a pressure of 5.5 atm in a 4.6 L container at 300.0K?

6. What is “STP”? (Standard Temperature and Pressure)
Standard Temperature = 0⁰C or K
Standard Pressure = 1 atm = 101.3kPa = 760 mmHg (Torr) = 101,325 Pa
At STP 1 mole of any gas occupies 22.4L (molar volume)

7. Summary of the Ideal Gas Law