In the system; Fe(OH)3(s) Fe3 +(aq) + 3OH-(aq), decreasing the concentration of OH- ions 1/3 times will cause the equilibrium concentration of Fe3 + to increase by:-


a) 3 times
b) 9 times
c) 18 times
d) 27 times
Kindly answer sir/mam.

Correct option is d, 27 times.

If concentration of OH- ions is decreased then according to Le Chatlier's principle, the reaction will move in forward direction to reestablish the equilibrium.

Kc = [Fe3+] [OH-]3

Assume that concentration of Fe3+ increases by n when the concentration of OH- is reduced 3 fold, 

Kc = n[Fe3+] [OH-]3 /(3)3 = n [Fe3+][OH-]3/27

Therefore, n [Fe3+][OH-]3/27 = [Fe3+] [OH-]3

and n =27


 

  • 95
What are you looking for?