Question
If the concentration of OH- ions in the reaction Fe(OH)3 (s) ⇌ Fe3+ (aq) + 3OH-(aq) is decreased by 1/4 times, then equilibrium concentration of Fe3+ will increase by
-
8 times
-
16 times
-
64 times
-
4 times
Solution
C.
64 times
The concentration of solids taken to be unity.
Fe(OH)3 (s) ⇌ Fe3+ (aq) + 3OH- (aq)
therefore,
K = [Fe3+][OH-]3
Hence, if OH- ion concentration is decreased by 1/4 times. then equilibrium concentration of Fe3+ will increase by 64 times.
