Ideal Gas Law

What is an Ideal gas?

An ideal gas is a theoretical gas composed of many randomly moving particles that do not interact with each other, don’t take up volume and perfectly obey the ideal gas law

What is the ideal gas law?

PV = nRT

What is pressure?

• Pressure is a measure of the collision of gas particles with the walls of its container

• OR

• Force per unit area

What is the SI unit of pressure?

Pascal (Pa) Or Newton per meter square (Nm^-2)

What is partial pressure?

The pressure exerted by each individual gas in a mixture of gases

How do you use mole fraction to in partial pressure calculations to find pressure exerted by a specific gas from the mixture of gases?

• Mole fraction is the number of moles of the selected gas over the sum of moles of all gasses in the mixture

The formula would be Px/P = nx/n

Where Px = pressure exerted by gas x 

Where nx = number of moles of gas x

what is the Kinetic Molecular Theory?

explains the behavior of gases at the molecular level. It’s based on several key assumptions about the motion and energy of particles.

What are the basic assumptions of the kinetic molecular theory?

1. Gas particles are in constant, random motion

2. Gas particles have negligible volume

3. No attractive or repulsive forces between gas particles

4. Collisions between particles are completely elastic

5. The average KE of the particles is proportional to the absolute temperature

What is gas pressure caused by?

Gas pressure is caused by collisions of its molecules with the walls of the container
    - The magnitude of the pressure is determined by how often and how forcefully the molecules strike           the walls

What is the absolute temperature of a gas?

A measure of the average kinetic energy of its molecules

What is the formula for Kinetic Energy?

KE = ½ mv²

What is Boyle’s law?

• the volume of a fixed amount of gas at constant temperature is inversely proportional to the pressure

• P1V1 = P2V2

What is Charles law?

• the volume of a fixed amount of gas maintained at constant pressure is directly proportional to its absolute temperature

• V1/T1 = V2/T2

What is Avogadro’s law?

• the volume of a gas maintained at constant temperature and pressure is directly proportional to the number of moles of the gas

• V1/n1 = V2/n2

When do real gases deviate from the ideal gas law?

• At low temperatures, gas molecules have lower kinetic energy and begin to experience some intermolecular attraction

• At high pressures, intermolecular attraction also comes into play because of the shorter distance seen when gas molecules are crowded

  • This means the combined volume of the gas molecules is not negligible relative to the container volume