What does Le Châtelier's Principle state about an equilibrium system when it is subject to change?

Le Châtelier's Principle is a fundamental concept in chemical equilibrium that describes how a system at equilibrium responds to external changes. When an equilibrium system experiences a change in concentration, temperature, or pressure, the principle states that the system will adjust in a direction that opposes that change to re-establish equilibrium.

Selecting the correct answer illustrates this principle perfectly: if a reactant or product is added, for instance, the system shifts to consume some of that substance. Similarly, if the temperature changes, the equilibrium will shift in a way that minimizes the effect of that temperature variation. In essence, the system seeks to neutralize any disturbance and restore a new state of balance.

This principle is critical for understanding not just basic reversible reactions but also more complex biological and industrial processes, where maintaining equilibrium can greatly affect yield, efficiency, and safety in reactions.