Ideal Gas Law

PV=nRT

Kinetic Molecular Theory

1. Gases have low density 2. Gases have elastic collisions 3. Gases have continuous random motion. 4. Gases have no attraction or repulsion 5. Kinetic energy is proportional to

temperature.

Properties of Gases

Pressure (P) Force of gas particles hitting the sides of their

container Volume (V)

The amount of space occupied by a gas Temperature (T)

The Kinetic Energy of gas molecules Mols (n)

The amount of gas molecules in a certain mass

Ideal Gas Law

“the mathematical relationship among pressure, volume, temperature, and the number of moles of a gas”

What are the observable relationships between these properties?

Pressure and Temperature Pressure and Volume Pressure and moles Volume and Temperature Volume and moles Temperature and moles

Partial Gas Laws

Boyle’s Law V = k / P

V : 1/P

Charle’s Law V = kT

V : T

Gay-Lussac’s Law P = k T

P : T

Avogadro’s Law Standard Molar volume

V : n

Ideal Gas Law

V : 1/P V : T V : n V : nT/P V = constant * nT/P PV = constant * nT Constant = R PV = nRT

Units: (for this class) V must be in Liters P must be in atm T must be in Kelvin n is always mols

Ideal Gas Constant = R 0.0821(L*atm) / (mol * K)

Ideal Gas Law Example

How many moles of gas are in 4.6 L of gas at 56kPa and 34oC?

Convert all units to the right units Volume: 4.6 L is in correct units Pressure: 56 kPa x (1atm/101.3kPa) = 0.55

atm Temperature: 34oC + 273 = 307K Write Ideal Gas Law Equation

PV = nRT

Ideal Gas Law Example

How many moles of gas are in 4.6 L of gas at 56Pa and 34oC?

PV = nRT Solve for unknown n = PV / (RT) Plug in numbers

n =(0.55 atm * 4.6 L) / (0.0821 * 307K)= 0.10mols

Simulation

http://www.chem.ufl.edu/~itl/2045/MH_sims/gas_sim.html