Le Chatelier's Principle is a rule that explains how a system at balance reacts when something changes.

When you make a change, the system tries to adjust itself to counter that change and find a new balance. There are different ways to see this principle in action through experiments.

1. Change in Concentration

One way to see this is by changing the amount of things in a reaction, called reactants or products. For example, in the reaction:

$\text{A} + \text{B} \rightleftharpoons \text{C}$

If we add more of A, the reaction speeds up. This causes C to increase until the system finds a new balance.

2. Change in Temperature

Temperature changes also show how Le Chatelier's Principle works. Take this reaction for example:

$\text{A} + \text{B} \rightleftharpoons \text{C} + \text{heat}$

If we increase the temperature, the balance shifts to the left. This means it will favor reactants as the system uses up the extra heat.

3. Change in Pressure

In reactions that involve gases, changing the pressure can change the balance too. Look at this reaction:

$\text{N}_2(g) + 3\text{H}_2(g) \rightleftharpoons 2\text{NH}_3(g)$

When you move to products, there are fewer gas particles. If the pressure goes up, the balance shifts to the right, which makes more NH3.

4. Catalysts

Catalysts are special substances that speed up reactions. They don’t change the balance, but they help the system get to balance faster. They speed up both the forward and backward reactions equally.

5. Color Changes

Some reactions involve colored substances. Changing concentration or temperature can cause visible color changes. For instance, in the cobalt(II) chloride reaction:

$\text{CoCl}_2 \cdot 6\text{H}_2\text{O} (s) \rightleftharpoons \text{Co}^{2+} (aq) + 6\text{H}_2\text{O} (l)$

When you dilute it or change the temperature, you can see a change in color. This shows how the balance shifts.

These experiments give clear evidence of how Le Chatelier's Principle works in real life.