Final answer:
The question cannot be correctly answered without knowing the stoichiometry of the specific reaction taking place. Assuming a complete reaction and stoichiometric balance, the initial mole ratio of reactants to products would dictate the final contents of the reactor. However, with the given options, none correspond to a clear stoichiometric outcome based on the initial conditions without additional context. Option number a is correct.
Step-by-step explanation:
To answer the question about the reactor contents after a certain reaction, we can draw from the principles of reaction stoichiometry and equilibrium discussed in the provided information. Considering the large equilibrium constant for the forward reaction and the small one for the reverse reaction, the reaction proceeds nearly to completion. The forward reaction involves the conversion of ethylene (C₂H₄) and hydrogen (H₂) into ethane (C₂H₆).
However, since the reaction goes almost to completion and there is a stoichiometric balance between reactants and products, option A seems correct only if ethane was produced from reacting all the ethylene and hydrogen initially present. Given the initial moles of ethylene and hydrogen, and the assumption that the reaction went to completion, it is not possible to determine the final contents without knowing the stoichiometry of the reaction.