## 2 HCl (aq) + 1 Ca(OH)2 (aq) → CaCl2 (aq) + H2O (ℓ)

Back to reactions list

## Stoichiometry

Enter a mass or volume in one of the boxes below. Upon hitting submit, the stoichiometric equivalents will be calculated for the remaining reactants and products. All gases are assumed to be at STP.

 Heat Added: kJ HCl            Mass: g or Solution Volume: mL of Concentration: mol/L Ca(OH)2        Mass: g or Solution Volume: mL of Concentration: mol/L CaCl2          Mass: g H2O            Mass: g

## Enthalpy of Reaction

[1ΔHf(CaCl2 (aq)) + 1ΔHf(H2O (ℓ))] - [2ΔHf(HCl (aq)) + 1ΔHf(Ca(OH)2 (aq))]
[1(-877.13) + 1(-285.83)] - [2(-167.15) + 1(-1002.81)] = 174.15 kJ
174.15 kJ     (endothermic)

## Entropy Change

[1ΔSf(CaCl2 (aq)) + 1ΔSf(H2O (ℓ))] - [2ΔSf(HCl (aq)) + 1ΔSf(Ca(OH)2 (aq))]
[1(59.82) + 1(69.91)] - [2(56.48) + 1(-74.64)] = 91.41 J/K
91.41 J/K     (increase in entropy)

## Free Energy of Reaction (at 298.15 K)

From ΔGf° values:
[1ΔGf(CaCl2 (aq)) + 1ΔGf(H2O (ℓ))] - [2ΔGf(HCl (aq)) + 1ΔGf(Ca(OH)2 (aq))]
[1(-816.04) + 1(-237.18)] - [2(-131.25) + 1(-868.1)] = 77.3799999999999 kJ
77.38 kJ     (nonspontaneous)

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

## Equilibrium Constant, K (at 298.15 K)

2.7724019346e-014
This process is not favorable at 25°C.

## Reference(s):

Ebbing, Darrell D. General Chemistry 3rd ed.; Houghton Mifflin Company: Boston, MA, 1990; p 90.