Metals and Equilibria: Le Chatelier's Principle

Metals and Equilibria: Le Chatelier’s Principle

  • Le Chatelier’s Principle is a chemical principle used to predict the effect of a change in conditions on chemical equilibria.
  • It states that if a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to counteract the change.
  • This can include changes in temperature, pressure or concentration.
  • An increase in temperature will favour the endothermic reaction (one which takes in heat from the surroundings). In turn, a decrease in temperature will favour the exothermic reaction (one which gives out heat to the surroundings).
  • Increasing pressure, meanwhile, causes the equilibrium position to shift towards the side of the reaction with fewer gas molecules. Decreasing pressure has the opposite effect.
  • A change in concentration will cause the equilibrium to shift as well. If you add more of a substance, the equilibrium will shift to remove it (towards the right if you add a reactant, to the left if you add a product). If you remove a substance, the equilibrium will shift to replace it.
  • The principle is used in the chemical industry to increase the yield of products from reactions. By understanding how changing the conditions can affect the direction of the reaction, chemists can manipulate the circumstances to their advantage.
  • It’s crucial to understand that while Le Chatelier’s Principle allows us to predict the direction of the shift, it does not tell us how much the equilibrium will shift - that is determined by the specificities of the reaction.
  • Le Chatelier’s principle is fundamental for understanding how metals react and reach equilibrium in different conditions. This can be applied in various processes including the extraction of iron in the blast furnace and the manufacture of ammonia by the Haber process.

Remember to also practise using this principle in calculations and different contexts, as a good understanding of Le Chatelier’s Principle is key for understanding chemical equilibria and, specifically, the equilibria of reactions involving metals.