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12.E: Practice Exercises - Chemical Equilibrium

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    523856
    • Anonymous
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    Additional Exercises

    1. What is the relationship between the Ksp expressions for a chemical reaction and its reverse chemical reaction?
    2. What is the relationship between the Kw value for H2O and its reverse chemical reaction?
    3. For the equilibrium \[PCl_{3}(g)+Cl_{2}(g)\rightleftharpoons PCl_{5}(g)+60kJ\nonumber \]
      list four stresses that serve to increase the amount of PCl5.
    4. For the equilibrium \[N_{2}O_{4}+57kJ\rightleftharpoons 2NO_{2}\nonumber \]
      list four stresses that serve to increase the amount of NO2.
    5. Does a very large Keq favor the reactants or the products? Explain your answer.
    6. Is the Keq for reactions that favor reactants large or small? Explain your answer.
    7. Write the Equilibrium Constant Expression for the following

    N2 (g) + 3 H2 (g) ⇌ 2 NH3 (g)

      1. Write the equation for NaCl dissolving in water.
      2. Write the equilibrium constant expression for NaCl dissolving in water. (Remember to leave out things that are not mixed or whose concentration remains constants- In this case, solids or liquids in the chemical equation.)
      3. Solve for the solubility equilibrium constant of NaCl if the concentrations of a saturated solution are [Na+] = 6.14 M and [Cl-] = 6.14 M

    Answers

    1. They are reciprocals of each other.
    2. increase the pressure; decrease the temperature; add PCl3; add Cl2; remove PCl5

    1. favor products because the numerator of the ratio for the Keq is larger than the denominator
    2. Keq = [NH3]2 / [N2][H2]3
      1. NaCl (s) ⇌ Na+ (aq) + Cl- (aq)
      2. Ksp = [Na+] [Cl-]
      3. Ksp = 37.7

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