Part i. you considered the equilibrium: fe3+(aq) + scn-(aq) fe(scn)2+(aq), and compared the color of the solutions in four test tubes. in the third test tube, you added 6 m naoh dropwise. how do you explain the formation of a precipitate and the shift in equilibrium in terms of lechatelier's principle? a. the addition of naoh produced the precipitate, fe(oh)3, which removed fe3+ from the system. to reduce the stress of the removal of fe3+ and to re-establish equilibrium, the system shifted to the left increasing [fe3+] and decreasing the [fe(scn)2+]. increasing the [fe3+] produced a yellow colored solution. b. the addition of naoh produced the precipitate, nascn, which removed scn- from the system. to reduce the stress of the removal of scn- and to re-establish equilibrium, the system shifted to the left increasing [scn-] and decreasing the [fe(scn)2+]. increasing the [scn-] produced a yellow colored solution. c. the addition of naoh produced the precipitate, fe(scn)(oh)2, which removed fe(scn)2+ from the system. the removal of fe(scn)2+ from the system caused the deep red color to disappear leaving only the yellow color.