To determine the equilibrium constant for the reaction

25.0 mL of a 0.0100 M aqueous solution of I₂ was extracted with 10.0 mL of CHCl₃. After extraction, spectrophotometric measurements revealed that the I₂ concentration of the aqueous layer was 1.12 x 10^-4 M. An aqueous solution that was 0.0100 M in I₂ and 0.100 M in KSCN was then prepared. After extraction of 25.0 mL of this solution with 10.0 mL of CHCl₃, the concentration of I₂ in the CHCl₃ layer was found from spectrophotometric measurement to be 1.02 x 10^-3 M.
(a) What is the distribution constant for I₂ between CHCl₃ and H₂O?
(b) What is the formation constant for I(SCN)₂^-?

Transcribed Image Text:

I, + 2SCN- = I(SCN), + I