FeF2 (s) → Fe+2 (aq) + 2 F-1 (aq)

Back to reactions list

 

Reaction Type:

Dissociation of an ionic compound in water

Enthalpy of Reaction

[1ΔHf(Fe+2 (aq)) + 2ΔHf(F-1 (aq))] - [1ΔHf(FeF2 (s))]
[1(-89.12) + 2(-332.6)] - [1(-702.91)] = -51.4100000000001 kJ
-51.41 kJ     (exothermic)

Entropy Change

[1ΔSf(Fe+2 (aq)) + 2ΔSf(F-1 (aq))] - [1ΔSf(FeF2 (s))]
[1(-137.65) + 2(-13.8)] - [1(86.99)] = -252.24 J/K
-252.24 J/K     (decrease in entropy)

Free Energy of Reaction (at 298.15 K)

From ΔGf° values:
[1ΔGf(Fe+2 (aq)) + 2ΔGf(F-1 (aq))] - [1ΔGf(FeF2 (s))]
[1(-78.87) + 2(-278.8)] - [1(-661.07)] = 24.6 kJ
24.60 kJ     (nonspontaneous)

From ΔG = ΔH - TΔS:
23.80 kJ     (nonspontaneous)

Equilibrium Constant, K (at 298.15 K)

4.898088776e-005
This process is not favorable at 25°C.

Enter an initial concentration for the ionic compound. Upon hitting submit, Ksp (4.898088776e-005) will be used to calculate the equilibrium concentration for all species.

FeF2 Fe+2 F-1
Initial M   0 0
Change -x +x +2x
Equilibrium