Write the Kc expression for the following reaction: Fe3+ + SCN- = FeSCN2+
To write the Kc expression for a reaction, you need to write the balanced chemical equation first. The balanced chemical equation for the reaction between Fe3+ and SCN- to form FeSCN2+ is:
Fe3+ + SCN- → FeSCN2+
Now, let's define the equilibrium expression, Kc, which represents the equilibrium concentrations of the reactants and products.
Kc = [FeSCN2+] / ([Fe3+][SCN-])
In this expression, the brackets denote the concentration of each species at equilibrium. The product, FeSCN2+, is in the numerator, while the reactants, Fe3+ and SCN-, are in the denominator. Remember to use the molar concentrations of each species when calculating Kc.
What's your trouble with this.
Concn products/concn reactants and the coefficients in the equation become exponents in the Kc expression.