Explanation:


The given reaction is 2HCl H2 Cl2. The equilibrium constant (Kc) for the reaction is 4×10^-34.




Writing the Expression for Kc:


The equilibrium constant expression for the given reaction is:


Kc = [H2][Cl2]/[HCl]^2




Interpreting Kc:


The value of Kc for the given reaction is very small (4×10^-34). This indicates that the concentration of products (H2 and Cl2) at equilibrium is extremely small compared to the concentration of reactants (HCl). Therefore, the reaction is a highly unfavorable one and the equilibrium lies far to the left-hand side.




Reaction Quotient:


The reaction quotient (Qc) can be calculated using the same expression as Kc. At equilibrium, the value of Qc is equal to Kc. If Qc is less than Kc, the reaction will proceed in the forward direction. If Qc is greater than Kc, the reaction will proceed in the backward direction.




Factors Affecting Kc:


The value of Kc for a reaction depends on the temperature and pressure of the system. Changes in temperature and pressure can shift the equilibrium position and alter the value of Kc.




Conclusion:


In summary, the given reaction has a very small equilibrium constant (Kc) value of 4×10^-34, indicating that the reaction is highly unfavorable and the equilibrium lies far to the left-hand side. Changes in temperature and pressure can affect the equilibrium position and alter the value of Kc.