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Le Châtelier's Principle

• Le Châtelier's principle explains how an equilibrium system responds to change, stating that:

  • If an equilibrium system is subjected to a change, it will shift to partially oppose that change.

Predicting Effects of Change on Equilibrium

• The effects of any change on an equilibrium system can be predicted:

  • This is based on Le Châtelier's principle, as well as collision theory and reaction rates.

Changes to System in Equilibrium

• Adding More Reactant:

  • Effect: Shifts equilibrium position to the right (net forward reaction).

• Adding More Product:

  • Effect: Shifts equilibrium position to the left (net reverse reaction).

Important Equilibria in Winemaking

• Several equilibria are critical in the wine production process:

  • Notably, equilibria involving sulfur dioxide and tartaric acid are of particular significance.

Carbon Dioxide and Global Warming

• Greenhouse Gas Effect:

  • Carbon dioxide (CO2) acts as a greenhouse gas, leading to the re-radiation of solar energy, which warms the Earth's surface.

  • Increased greenhouse gases are predicted to elevate global temperatures.

• Oceans and Carbon Dioxide Concentrations:

  • The oceans help maintain stable atmospheric CO2 levels due to the gas's slight solubility in water, which occurs through various reversible processes.

• Impact of Increased CO2:

  • Greater atmospheric CO2 concentration results in more CO2 dissolving in oceans, forming carbonic acid.

  • Increased carbonic acid raises the concentration of hydronium ions (H3O+) in seawater, consequently lowering its pH.

• Ocean Acidity and Marine Life:

  • Higher ocean acidity leads to reactions where hydroxy ions react with carbonate ions.

  • Reduced carbonate ion concentration hinders marine organisms, impairing their ability to form and maintain calcium carbonate structures.