2 HBr (aq) + 1 CdCO3 (s) → CdBr2 (aq) + H2O (ℓ) + 1 CO2 (g)

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Reaction Type:

Double Displacement/Decomposition of a Carbonate

Stoichiometry

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HBr            Mass: g  or Solution Volume: mL of Concentration: mol/L
CdCO3          Mass: g
CdBr2          Mass: g
H2O            Mass: g
CO2            Mass: g  or Gas Volume: L

Enthalpy of Reaction

[1ΔHf(CdBr2 (aq)) + 1ΔHf(H2O (ℓ)) + 1ΔHf(CO2 (g))] - [2ΔHf(HBr (aq)) + 1ΔHf(CdCO3 (s))]
[1(-75.9) + 1(-285.83) + 1(-393.51)] - [2(-121.55) + 1(-750.61)] = 238.47 kJ
238.47 kJ     (endothermic)

Entropy Change

[1ΔSf(CdBr2 (aq)) + 1ΔSf(H2O (ℓ)) + 1ΔSf(CO2 (g))] - [2ΔSf(HBr (aq)) + 1ΔSf(CdCO3 (s))]
[1(231.26) + 1(69.91) + 1(213.68)] - [2(82.42) + 1(92.47)] = 257.54 J/K
257.54 J/K     (increase in entropy)

Free Energy of Reaction (at 298.15 K)

From ΔGf° values:
[1ΔGf(CdBr2 (aq)) + 1ΔGf(H2O (ℓ)) + 1ΔGf(CO2 (g))] - [2ΔGf(HBr (aq)) + 1ΔGf(CdCO3 (s))]
[1(-77.6) + 1(-237.18) + 1(-394.38)] - [2(-103.97) + 1(-669.44)] = 168.22 kJ
168.22 kJ     (nonspontaneous)

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

Equilibrium Constant, K (at 298.15 K)

3.3689238699e-030
This process is not favorable at 25°C.