question_answer 1)

Equilibrium constant \[{{K}_{c}}\] for the reaction, \[{{N}_{2}}(g)+3{{H}_{2}}(g)\rightleftharpoons 2N{{H}_{3}}(g)\] at 500 K is 0.061. At particular time, the analysis shows that the composition of the reaction mixture is: \[3.0mol{{L}^{-1}}\]of\[{{N}_{2}};\,\,2.0mol\,{{L}^{-1}}\]of \[{{H}_{2}};0.50mol{{L}^{-1}}\] of\[N{{H}_{3}}\] . Is the reaction at equilibrium? If not, in which direction does the reaction tend to proceed to reach the equilibrium?

Answer:

Information shadow: Reaction: \[{{N}_{2}}(g)+3{{H}_{2}}(g)\rightleftharpoons 2N{{H}_{3}}(g)\] \[{{K}_{c}}=0.061at500K\] Composition of reaction mixture: \[[{{N}_{2}}]=3mol{{L}^{-1}};[{{H}_{2}}]=2mol{{L}^{-1}},[N{{H}_{3}}]=0.5mol\,{{L}^{-1}}\] Problem solving strategy: Reaction quotient Q can be calculated as: \[Q=\frac{{{[N{{H}_{3}}]}^{2}}}{[{{N}_{2}}]{{[{{H}_{2}}]}^{3}}}\] Comparison of Q with K will decide whether the reaction is at equilibrium or not. Working it out: \[Q=\frac{{{[0.5]}^{2}}}{3\times {{(2)}^{3}}}=\frac{0.25}{24}=0.01\] \[Q\ne K;\]the reaction is not at equilibrium. \[Q>{{K}_{c}};\]the net reaction will be towards right.