Reversible reactions and equilibrium

• Reversible reaction


  A reaction with a double arrow in the middle, indicating it can react in both forward and backward directions
• Reversible reaction


  1. Forward reaction

  2. Backward reaction
• Equilibrium


  The point where the forward and backward reactions are occurring at the same rate, so there is no overall change in concentrations
• Position of equilibrium


  The relative concentrations of reactants and products at equilibrium, which can shift left or right depending on conditions
• Adding heat to the reaction

  Encourages the forward reaction, shifting the position of equilibrium to the right
• Cooling the reaction


  Pushes the position of equilibrium back to the left
• Reversible reactions can only reach equilibrium in a closed system, where no reactants or products can escape</b>
• Exothermic


  A reaction that releases heat energy
• Endothermic


  A reaction that absorbs heat energy
• Reversible reactions are always exothermic in one direction and endothermic in the other
• Hydrated means water is present, anhydrous means no water is present
• Equilibrium


  The state at which the rates of the forward and backward reactions are equal
• Dynamic equilibrium


  A state in which the concentrations of the reactants and products are constant, but the reactions are still occurring