Question

The reaction F + G = H is at equilibrium, under standard conditions.

(a) Calculate ∆Go’ if [F] = 2mM, [G] = 3 mM, and [H] = 9 mM

(b) What happens to ∆Go’ if the solution is at equilibrium at twice this concentration of F?

(c) What happens to ∆Go’ if the solution is at equilibrium at twice this concentration of H?

(d) Does this violate LeChatelier’s Principle?

Answer 1

Fo the given reaction,

(a) dGo = -RTlnK

            = -RT ln([H]/[F][G])

            = -8.314 x 298 ln(9/2 x 3)           

            = -1.003 kJ/mol

(b) when [F] = 4 mM

dGo = -RTlnK

            = -RT ln([H]/[F][G])

            = -8.314 x 298 ln(9/4 x 3)           

            = 743.27 kJ/mol

(c) when [H] = 18 mM

dGo = -RTlnK

            = -RT ln([H]/[F][G])

            = -8.314 x 298 ln(18/2 x 3)           

            = -2.72 kJ/mol

(d) Yes, this violates the LeChatellier's principle, according to which when the concentration at one end increase the concentration at other end would increase accordingly.