Chemical Equilibrium – Ch. 6
    1. Consider the following reaction:      
             N (g)  +  3  H  (g) ⇌  2  NH  (g) 
              2        2        3
       a.  Write the equilibrium expression (K and K )
                                       p
       b.  What is the value of K  at 25°C if the equilibrium pressures for 
                         p
          N, H  and NH  were 1.8 atm, 0.5 atm and 0.017 atm 
           2  2     3
       respectively.  
       c.  What is the value of K at 25°C? K  = K(RT)Δn
                                 p
       d.  Does the reaction favor reactants or products?
     Chemical Equilibrium – Ch. 6
                          Equilibrium Expression
                          Equilibrium Expression
                               ⇌
                           jA + kB    lC + mD
                               ⇌
                           jA + kB    lC + mD
                               K = 
                               K = 
                          Pure solids and liquids 
                          Pure solids and liquids 
                         are given the value of 1 in the 
                         are given the value of 1 in the 
                             expression
                             expression
                   Where does the equilibrium lie?
                   Where does the equilibrium lie?
                  K > 1 ⇒ The products are favored
                  K > 1 ⇒ The products are favored
                 K < 1 ⇒ The reactants are favored  
                 K < 1 ⇒ The reactants are favored  
  Chemical Equilibrium – Ch. 6
       Chemical Equilibrium – Ch. 6
       2.  Which reaction does the K = K ? 
                                                      p
             a.  P  (s) + 6 Cl (g)  ⇌ 4 PCl (g)
                   4              2                  3 
             b.  H O (l) ⇌  H O (g)
                    2              2
             c.  H (g)  +  Cl (g)  ⇌   2 HCl (g)
                    2             2 
             d.  C H (g) + 5 O (g) ⇌  3 CO (g) + 4 H O (g)
                    3  8             2                  2             2
                                                       Δn
                                                       Δn
                                             Kp = K(RT)
                                             Kp = K(RT)
     Chemical Equilibrium – Ch. 6
     3.  Given the following information:
             H(g) + I (g) ⇌ 2 HI(g)     K = 54.0
               2      2
             N(g) + 3 H (g) ⇌ 2 NH (g) K = 96.0
               2        2           3
         Determine the value of the equilibrium constant for the following 
         reaction:
             2 NH (g) + 3 I (g) ⇌ 6 HI(g) + N (g)
                  3        2                 2