Potassium thiocyanate, KSCN, is often used to detect the presence of Fe³⁺ ions in solution through the formation of the red Fe(H₂O)₅SCN²⁺ (or, more simply, FeSCN²⁺; Kf=8.9X10²). What is [Fe³⁺] when 0.50 L each of 0.0015 M Fe(NO₃)₃ and 0.20 M KSCN are mixed?