Standard solution of FeSCN2+FeSCN2+ is prepared by combining 9.09.0 mL of 0.200.20 M Fe(NO3)3Fe(NO3)3 with 1.01.0 mL of 0.00200.0020 M KSCN. KSCN. The equation for the reaction is as follows. Fe(NO3)3+KSCN↽−−⇀FeSCN2++KNO3+2NO−3 Fe(NO3)3+KSCN↽−−⇀FeSCN2++KNO3+2NO3− What allows us to assume that the reaction goes essentially to completion? The reaction quotient Q is greater than Kc. Kc. The concentration of Fe(NO3)3Fe(NO3)3 is much higher than the concentration of KSCN. KSCN. The excess Fe3+Fe3+ prevents the formation of the neutral Fe(SCN)3.Fe(SCN)3. The equlibrium reaction has a very high Kc. Kc. Under the conditions given, Le Châtelier's principle dictates that the reaction shifts to the left. Based on that assumption, what is the equilibrium concentration of FeSCN2+?

The equilibrium concentration of FeSCN²⁺ is 0.0002 M

Explanation:

Given data:

9 mL of 0.2 M of Fe(NO)₃

1 mL of 0.002 M of KSCN

Question: What is the equilibrium concentration of FeSCN²⁺

Calculate the initial millimoles of Fe(NO₃)₃:

Initial millimoles of KSCN:

Total volume of solution:

Vtotal = 1 + 9 = 10 mL

Initial concentration of Fe(NO₃)₃:

Initial concentration of KSCN:

The reaction:

                SCN⁻      +         Fe³⁺ →          FeSCN²⁺

I                0.0002              0.18               0

C               -0.0002             -0.0002       0.0002

E               0                         0.1798          0.0002

As you see the equilibrium concentration of FeSCN²⁺ is 0.0002 M

icc, international association for cereal chemistry

the electrical  conductivity  of asolution  of an electrolyte is measured by determining the resistance of thesolution  between two flat or cylindrical electrodes separated by a fixed distance.