Final answer:
According to Le Chatelier's principle, the removal of SCN⁻ by precipitation with silver nitrate would shift the equilibrium to restore SCN⁻ concentration, also affecting Fe³⁺. The initial assumption that all SCN⁻ is in the form of Fe(SCN)²⁺ can be confirmed by calculations showing that concentrations are consistent with the expected equilibrium constant.
Step-by-step explanation:
The question pertains to a chemical equilibrium system in which there is a reaction between iron(III) ions (Fe³⁺) and thiocyanate ions (SCN⁻) to form the complex ion Fe(SCN)²⁺. The original assumption that all of the SCN⁻ is in the form of Fe(SCN)²⁺ is being questioned based on a calculation from prior information. In this scenario, Le Chatelier's principle is applied: when SCN⁻ is removed due to precipitation with silver nitrate, forming AgSCN(s), the equilibrium shifts to restore some of the SCN⁻ concentration. This shift would also affect the concentration of Fe³⁺, according to the principle. The calculation should justify whether the concentration changes are consistent with the original assumption that all SCN⁻ forms Fe(SCN)²⁺, which would typically be supported by finding that the resulting concentrations conform to the expected equilibrium constant (K), suggesting no excess SCN⁻ was initially present.