Hg2I2 (s) → Hg2+2 (aq) + 2 I-1 (aq)

Back to reactions list

 

Reaction Type:

Dissociation of an ionic compound in water

Enthalpy of Reaction

[1ΔHf(Hg2+2 (aq)) + 2ΔHf(I-1 (aq))] - [1ΔHf(Hg2I2 (s))]
[1(172.4) + 2(-55.19)] - [1(-121.34)] = 183.36 kJ
183.36 kJ     (endothermic)

Entropy Change

[1ΔSf(Hg2+2 (aq)) + 2ΔSf(I-1 (aq))] - [1ΔSf(Hg2I2 (s))]
[1(84.5) + 2(111.29)] - [1(242.67)] = 64.4100000000001 J/K
64.41 J/K     (increase in entropy)

Free Energy of Reaction (at 298.15 K)

From ΔGf° values:
[1ΔGf(Hg2+2 (aq)) + 2ΔGf(I-1 (aq))] - [1ΔGf(Hg2I2 (s))]
[1(153.5) + 2(-51.59)] - [1(-111)] = 161.32 kJ
161.32 kJ     (nonspontaneous)

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

Equilibrium Constant, K (at 298.15 K)

5.4498702204e-029
This process is not favorable at 25°C.

Enter an initial concentration for the ionic compound. Upon hitting submit, Ksp (5.4498702204e-029) will be used to calculate the equilibrium concentration for all species.

Hg2I2 Hg2+2 I-1
Initial M   0 0
Change -x +x +2x
Equilibrium