Objective

By the end of this lesson, you will be able to explain the concept of chemical equilibrium in aqueous solutions and apply Le Chatelier's principle to predict the effects of changes in concentration, pressure, and temperature on the equilibrium position of a reaction.

Materials and Prep

Materials: - Pen and paper - Water - Clear container - Food coloring - Stirring rod or spoon

Prep: - Familiarize yourself with the concept of chemical equilibrium and Le Chatelier's principle.

Activities

1. Create a saturated solution of water and a colored solute (food coloring) in a clear container. Observe the initial color and document your observations.

2. Stir the solution and note any changes in color. Record your observations.

3. Discuss how the system reaches a dynamic equilibrium and how Le Chatelier's principle applies to the changes observed in the solution.

Twelfth Grade Talking Points

• Le Chatelier's principle states, "If a system at equilibrium is disturbed by a change in temperature, pressure, or concentration, the system will shift its position to counteract the effect of the disturbance."
• Chemical equilibrium occurs when the rates of the forward and reverse reactions are equal, resulting in a dynamic balance where the concentrations of reactants and products remain constant over time.
• When a stress is applied to a system at equilibrium, the system responds by adjusting the concentrations of reactants and products to partially counteract the stress and restore equilibrium.