Pressure and reversible reactions

• What should you be able to describe by the end of this video?

  The effect of pressure on equilibrium
• What happens to a system at equilibrium when conditions change?

  The system responds to counteract the change
• What principle explains the response of a system at equilibrium to changes?

  Le Chatelier's principle
• What is the focus of this video regarding pressure?

  The effect of pressure on reversible reactions
• What does the pressure of a gas depend on?

  The number of molecules present
• How does the number of molecules affect gas pressure?

  More molecules result in higher pressure
• In the reaction of nitrogen and hydrogen, how many molecules are on the left side?

  Four molecules
• How many molecules of ammonia are produced in the nitrogen and hydrogen reaction?

  Two molecules
• What happens to the equilibrium position if pressure is increased?

  It shifts to the side with fewer molecules
• What happens to the equilibrium position if pressure is decreased?

  It shifts to the side with more molecules
• In the nitrogen and hydrogen reaction, what happens if pressure is increased?

  The equilibrium shifts to the right side
• In the nitrogen and hydrogen reaction, what happens if pressure is decreased?

  The equilibrium shifts to the left side
• In the iodine and hydrogen reaction, how many molecules are on each side?

  Two molecules on each side
• What is the effect of changing pressure on the iodine and hydrogen reaction?

  It has no effect on the equilibrium position
• What are the rules for pressure effects on reversible reactions?

  • Increase pressure: equilibrium shifts to fewer molecules
  • Decrease pressure: equilibrium shifts to more molecules
• What types of reactions are affected by pressure changes?

  • Reactions involving gases
  • Reversible reactions