Chatelier's Principle

Page
1

Slide 1

Le Chatelier’s Principle

Slide 2

LeChatelier’s Principle

When a system at

equilibrium is placed under

stress, the system will

undergo a change in such

a way as to relieve that

stress and restore a

state of equilibrium.

Henry Le Chatelier

Slide 3

Le Chatelier Translated

When you take something away from a system at equilibrium, the system shifts in such a way as to replace some what you’ve taken away.

When you add something to a system at equilibrium, the system shifts in such a way as to use up some of what you’ve added.

Slide 4

LeChatelier Example

A closed container of ice and water is at equilibrium. Then, the temperature is raised.

Ice + Energy  Water

The system temporarily shifts to the _ to restore equilibrium.

right

Slide 5

LeChatelier Example #2

A closed container of N2O4 and NO2 is at equilibrium. NO2 is added to the container.

N2O4 (g) + Energy  2 NO2 (g)

The system temporarily shifts to the _ to restore equilibrium.

left

Slide 6

LeChatelier Example #3

A closed container of water and its vapor is at equilibrium. Vapor is removed from the system.

water + Energy  vapor

The system temporarily shifts to the _ to restore equilibrium.

right

Slide 7

LeChatelier Example #4

A closed container of N2O4 and NO2 is at equilibrium. The pressure is increased.

N2O4 (g) + Energy  2 NO2 (g)

The system temporarily shifts to the _ to restore equilibrium, because there are fewer moles of gas on that side of the equation.

left