(NH4)3PO4 (aq) + 3 KOH (s) → K3PO4 (aq) + 3 H2O (ℓ) + 3 NH3 (g)

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Reaction Type:

Double Displacement/Decomposition of Ammonium Hydroxide

Stoichiometry

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(NH4)3PO4      Mass: g  or Solution Volume: mL of Concentration: mol/L
KOH            Mass: g
K3PO4          Mass: g
H2O            Mass: g
NH3            Mass: g  or Gas Volume: L
Heat Released: kJ

Enthalpy of Reaction

[1ΔHf(K3PO4 (aq)) + 3ΔHf(H2O (ℓ)) + 3ΔHf(NH3 (g))] - [1ΔHf((NH4)3PO4 (aq)) + 3ΔHf(KOH (s))]
[1(-2034.58) + 3(-285.83) + 3(-46.11)] - [1(-1674.91) + 3(-425.85)] = -77.9400000000001 kJ
-77.94 kJ     (exothermic)

Entropy Change

[1ΔSf(K3PO4 (aq)) + 3ΔSf(H2O (ℓ)) + 3ΔSf(NH3 (g))] - [1ΔSf((NH4)3PO4 (aq)) + 3ΔSf(KOH (s))]
[1(85.75) + 3(69.91) + 3(192.34)] - [1(118.42) + 3(78.87)] = 517.47 J/K
517.47 J/K     (increase in entropy)

Free Energy of Reaction (at 298.15 K)

From ΔGf° values:
[1ΔGf(K3PO4 (aq)) + 3ΔGf(H2O (ℓ)) + 3ΔGf(NH3 (g))] - [1ΔGf((NH4)3PO4 (aq)) + 3ΔGf(KOH (s))]
[1(-1868.7) + 3(-237.18) + 3(-16.48)] - [1(-1256.91) + 3(-379.07)] = -235.56 kJ
-235.56 kJ     (spontaneous)

From ΔG = ΔH - TΔS:
-232.22 kJ     (spontaneous)

Equilibrium Constant, K (at 298.15 K)

1.864759537e+041
This process is favorable at 25°C.