Chemistry Reversible reactions

• What is a reversible reaction?

  Products can reform reactants.
• How is a reversible reaction represented in an equation?

  Using a reversible arrow (⇌).
• What happens if a reversible reaction is exothermic in one direction?

  It will be endothermic in the other direction.
• How much energy is transferred in each direction of a reversible reaction?

  The same amount of energy is transferred.
• What is the state of hydrated copper sulfate?

  It is blue.
• What is the state of anhydrous copper sulfate?

  It is white.
• What occurs when a reversible reaction reaches dynamic equilibrium?

  Forward and backward reactions happen at the same rate.
• What remains constant in dynamic equilibrium?

  The concentrations of all reactants and products.
• What can be observed in a reaction at dynamic equilibrium?

  No changes can be observed.
• How can the position of equilibrium be changed?

  By changing the conditions of the reaction.
• Why is increasing the amount of products formed desirable in industry?

  To improve production rates and sales.
• What does Le Châtelier’s Principle state?

  Equilibrium will shift to oppose a change.
• What happens if the concentration of one substance in an equilibrium reaction is changed?

  The reaction is no longer at equilibrium.
• What happens if the concentration of a substance is increased in an equilibrium reaction?

  Equilibrium will shift to reduce that concentration.
• For the reaction A + B ⇌ C + D, what happens if the concentration of A is increased?

  Equilibrium shifts forward to increase C and D.
• What happens to the position of equilibrium if the temperature of a system at equilibrium is changed?

  It will shift to oppose the change.
• What occurs when the temperature is increased in a system at equilibrium?

  Equilibrium shifts in the endothermic direction.
• What happens if the pressure of a system involving gases is increased?

  Equilibrium shifts to the direction of fewer moles of gas.
• Why does equilibrium shift in the direction of fewer moles of gas?

  To reduce the pressure in the system.