number of moles of KSCN = 1.9 * 10^-3 * 14 /1000 = 2.66 *
10^-5
number of moles of Fe(NO3)3 = 9.1*10^-2 * 7.8 /1000 =
7.098*10^-4
3 KSCN + Fe(NO3)3 ----------> Fe(SCN)3 + 3 KNO3
1mole of Fe(NO3)3 requirea 3 moles of KSCN
2.66 * 10^-5 moles of KSCN requires (1/3)*2.66 * 10^-5
                                                                  Â
= 8.867 * 10^-6
remaining moles of Fe(NO3)3 = 7.098*10^-4 - 8.867 * 10^-6 =
7.093 * 10^-4
concentration of Fe+3 = (7.093 * 10^-4) * 1000 /
(14+7.8+11.7)
                                      Â
= 0.02117 M
