10. the equilibrium constant

• How is total pressure in a reaction defined?

  Sum of all partial pressures of gases
• What does the symbol $P_{SO_2} \text{ and } P_{Cl_2}$ represent?


  Partial pressures of SO2 and Cl2
• Why can't the partial pressure of Cl2 be used to determine the pressure of SO2Cl2?

  Cl2 is a reactant and decreases in value
• How do you calculate the partial pressure of SO2 given the total pressure and partial pressure of Cl2?

  Subtract Cl2's pressure from total pressure
• What is the mole fraction of a gas?

  Proportion of a gas in a mixture
• 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 using mole fraction?

  Partial pressure = mole fraction × total pressure
• What is the process for calculating the partial pressure of SO2Cl2 in a reaction?

  1. Identify initial moles of each gas.
  2. Use an ICE table for changes.
  3. Calculate equilibrium moles.
  4. Determine mole fraction of SO2Cl2.
  5. Calculate partial pressure using mole fraction and total pressure.
• How do you determine the change in moles for reactants in an equilibrium reaction?

  Reactants decrease in moles
• What does the ICE table stand for in equilibrium calculations?

  Initial, Change, Equilibrium
• Why is it important to track changes in moles during a reaction?

  It affects equilibrium calculations
• How do you calculate the final partial pressure of SO2Cl2?

  Multiply mole fraction by total pressure
• What are the steps to calculate the equilibrium moles using an ICE table?

  1. Write initial moles of each gas.
  2. Record changes in moles.
  3. Calculate equilibrium moles.
  4. Use the equilibrium moles for further calculations.
• How is the mole fraction calculated?

  It is the number of moles divided by total moles
• How do you calculate partial pressure from mole fraction?

  Multiply mole fraction by total pressure
• What is the KP equilibrium constant used for?

  To calculate gas equilibrium reactions
• What is the difference between KP and KC?

  KP uses partial pressures, KC uses concentrations
• How is the KP expression formulated?

  Products' partial pressures divided by reactants' partial pressures
• What is the KP expression for the reaction 2A + B ⇌ C + D?

  Kp= (ppC) (ppD) / (ppA)^2 (ppB)
• How do you determine the units for KP?

  Cancel units of pressure in the expression
• What happens to KP if temperature changes?

  It changes with temperature
• How does temperature affect equilibrium pressures?

  Increasing temperature shifts equilibrium right
• What is Le Chatelier's principle regarding temperature changes?

  Equilibrium shifts to counteract temperature change
• What happens to KP if the temperature increases for an exothermic reaction?

  KP decreases
• What happens to KP if the temperature decreases for an exothermic reaction?

  KP increases
• How does pressure affect the value of KP?

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

  No effect on the value of KP
• What is the role of a catalyst in a reaction?

  It speeds up the rate of reaction
• What are the key factors affecting the value of KP?

  • Temperature
  • Pressure
  • Catalysts
• How does the KP expression relate to equilibrium reactions?

  • KP is calculated using partial pressures
  • Products over reactants
  • Reflects the state of equilibrium
• What is the significance of equilibrium constants like KP and KC?

  • Indicates the extent of a reaction
  • Helps predict the direction of the reaction
  • Useful for calculating concentrations or pressures at equilibrium