Use the reaction below to answer the question. A solution at equlibrium is yellow-orange. The concentration of Fe3+ (iron) ions in increased by a moderate amount. What direction will the reaction shift and what color will the solution become?

Question

Use the reaction below to answer the question. A solution at equlibrium is yellow-orange. The concentration of Fe3+ (iron) ions in increased by a moderate amount. What direction will the reaction shift and what color will the solution become?

FeSCN^2(aq) Fe^3(aq)+SCN-(aq)
in the reaction, FeSCN^2 ions are red, Fe^3+ ions are pale yellow, and SCN- ions are colorless.
a) Shift left and become more yellow
b) Shift left and become more red/orange
c) Shift right and become more red/orange
d) Shift right and become more yellow

Answer 1

The addition of Fe3+ ions will disturb the equilibrium of the reaction. According to Le Chatelier's principle, the system will shift in a direction that counteracts the change. Since Fe3+ ions are on the reactant side, the reaction will shift to the right to consume some of the added Fe3+ ions. As a result, more FeSCN2+ ions will be formed, which are red in color. Therefore, the solution will become more red/orange.

The correct answer is c) Shift right and become more red/orange.