Equilibrium

A reversible reaction is one where the products of the reaction can themselves react to produce the original reactants

• has to take place in a 'closed system'
• = forward reaction going at exactly the same rate as the backward one
• doesn't mean the amounts of reactants + products are equal
• NOTE Adding a catalyst speeds up the time taken to get to equilibrium
  
• 3 Things can change the position of it:
  • Temperature
  • Pressure
  • Concentration

• 3 Things can change the position of it:
  • Temperature
    • all reactions are exothermic in 1 direction + endothermic in the other
    • if you decrease the tmep the equilibrium will move to try + increase it = the equilibrium moves in the exothermic direction to produce more heat
  • Pressure
    • if you increase the pressure the equilibrium tries to reduce it
    • it moves in the direction where there are fewer moles of gas
  • Concentration
    • if you increase the concentration of the reactants the equilibrium tries to decrease it by shifting to the right
    • if you increase the concentration of the products the equilibrium tries to reduce it by shifting to the left