Equilibrium

Definition

Equilibrium is a state in which opposing forces or influences are balanced. In biological systems, it often refers to the balance of chemical concentrations within cells and ecosystems.

5 Must Know Facts For Your Next Test

1. In chemical reactions, equilibrium is reached when the rate of the forward reaction equals the rate of the reverse reaction.
2. Dynamic equilibrium in ecosystems involves a balance between organisms and their environment, including nutrient cycles and energy flow.
3. Equilibrium does not mean that reactants and products are equal in concentration but that their rates of formation and decomposition are constant.
4. Le Chatelier's Principle states that if an external change is applied to a system at equilibrium, the system will adjust to partially counteract the change.
5. Homeostasis in living organisms is an example of dynamic equilibrium where internal conditions remain stable despite external changes.

Review Questions

• What happens to a chemical reaction at equilibrium?
• How does dynamic equilibrium apply to ecosystems?
• Explain how Le Chatelier's Principle affects a system in equilibrium.

Related terms

Dynamic Equilibrium: A state of balance between continuing processes.

Homeostasis:

The ability of an organism to maintain internal stability.

Le Chatelier's Principle: A principle stating that if a constraint is applied to a system in equilibrium, the system will adjust to counteract the constraint.