Question

With the initial concentrations of [SCN]= 0.0005 M, [Fe3+]= 0.000698M, and [Fe(SCN)2+]=0.000M, determine the value of k if the [Fe(SCN)2+] at equilibrium is 0.0000866M.

Fe3+(aq) + SCN (aq) = Fe(SCN)2+ (aq)

Answer 1

..............Fe^3+ + SCN^-==>FeSCN^2+
initial.....0.0005...0.000698...0
change.........-x......-x.......+x
equil... 0.0005-x..0.000698-x...8.66E-5

so x must be 8.66E-5 which allows you to determine SCN^- and Fe(III) at equil then plug into the Kc expression to determine k.

Answer 2

210