Equilibrium Constant Kp

• What is the total pressure in a reaction?

  Sum of all partial pressures of gases
• How is partial pressure represented in equations?

  With a lowercase 'p' and curly brackets
• How is the mole fraction of a gas calculated?

  Number of moles of gas divided by total moles
• What is the formula for calculating partial pressure?

  Mole fraction x total pressure
• What does the change in moles indicate for reactants in a reaction?

  Reactants decrease in moles
• What are the key steps in calculating equilibrium pressures using mole fractions?

  1. Determine initial moles of each gas
  2. Use ICE table to track changes
  3. Calculate equilibrium moles
  4. Find mole fractions
  5. Calculate partial pressures using mole fractions
• What does KP use instead of concentration?

  Partial pressure
• How is the KP expression structured?

  Products over reactants using partial pressures
• Why must figures used in KP calculations be at equilibrium?

  Because KP is defined at equilibrium conditions
• How are units for KP determined?

  By writing and canceling units of pressures
• What happens to KP if temperature changes?

  KP is only valid at one temperature
• How does increasing temperature affect KP for an exothermic reaction?

  It causes KP to decrease
• What does Le Chatelier's principle state about temperature changes?

  Equilibrium shifts to counteract the change
• What happens to equilibrium if temperature is decreased in an exothermic reaction?

  Equilibrium shifts to the right
• How does pressure affect the value of KP?

  KP is unaffected by pressure changes
• What is the effect of adding a catalyst on KP?

  Catalysts do not affect KP value
• What is the primary role of a catalyst in a reaction?

  To speed up the rate of reaction
• What is the relationship between KP and KC?

  KP is for gases, KC is for concentrations
• What is the KP expression for the reaction 2A + B ⇌ C + D?

  $\frac{\left(ppC\right)\left(ppD\right)}{\left(ppA\right)^2\left(ppB\right)}$