Question

For the following reaction:

CrO4^2- + H2O ----- HCrO4 + OH
Calculate the equilibrium constant.
(Chromic acid is H2CrO4, a diprotic acid, Ka1= 1.80x10^-1, Ka2=3.20x10^-7 & Kw=1.00x10^-14).

Answer 1

The equilibrium constant for the given reaction can be calculated using the concentrations of the reactants and products. By utilizing the dissociation constants of chromic acid, we can determine the concentrations of the relevant species and substitute them into the equilibrium constant expression to obtain the value of K.

Step-by-step explanation:

The equilibrium constant for the given reaction can be calculated using the formula:

K = [HCrO4][OH]/[CrO42-][H2O]

Since the concentration of water remains constant, it can be omitted from the equation. The equilibrium constant can then be written as:

K = [HCrO4][OH]/[CrO42-]

Using the given values for the dissociation constants (Ka1 and Ka2) of chromic acid (H2CrO4), we can calculate the concentrations of [HCrO4] and [CrO42-]. Finally, substitute these concentrations into the equilibrium constant expression to obtain the value of K.