Reversible reactions

• Reversible reaction


  a reaction that its products can react together to produce the original reactants
• The reaction mixture of a reversible reaction may contain reactants and products and their proportions may be changed by altering the reaction conditions
• hydrated copper sulfate <-> anhydrous copper sulfate + water


  CuSO4．5H2O <-> CuSO4 + 5H2O

  forward: endothermic

  reverse: exothermic
• When a reversible reaction happens in a closed system, it reaches a dynamic equilibrium
• Dynamic equilibrium

  ->forward and reverse reactions happen at the same rate

  ->concentrations of the substances are constant
• The equilibrium position of a reversible reaction is a measure of the concentrations of reacting substances at equilibrium
• Le Chatelier’s Principle

  If an equilibrium is disturbed by changing the conditions, the position of equilibrium moves to counteract the change
• Factors that affect the reaction conditions

  ->pressure

  ->concentration

  ->temperature
• If the concentration of the reactant is increased, the equilibrium position moves away from this reactant