In the presence of excess thiocyanate ion, SCN-, the following reaction is first order in iron(III) ion, Fe3+. The rate constant is 1.27/s.
Fe3+(aq)+SCN-(aq) – Fe(SCN)2+(aq)
If 35.6% of the reaction is required to obtain a noticeable color from the formation of the Fe(SCN)2+ ion, how many seconds are required?
Time = s