NaOH (aq) + 1 NH4Br (aq) → NaBr (aq) + NH3 (g) + 1 H2O (ℓ)

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Stoichiometry

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Heat Added: kJ
NaOH           Mass: g  or Solution Volume: mL of Concentration: mol/L
NH4Br          Mass: g  or Solution Volume: mL of Concentration: mol/L
NaBr           Mass: g
NH3            Mass: g  or Gas Volume: L
H2O            Mass: g

Enthalpy of Reaction

[1ΔHf(NaBr (aq)) + 1ΔHf(NH3 (g)) + 1ΔHf(H2O (ℓ))] - [1ΔHf(NaOH (aq)) + 1ΔHf(NH4Br (aq))]
[1(-361.65) + 1(-46.11) + 1(-285.83)] - [1(-470.09) + 1(-254.06)] = 30.5600000000002 kJ
30.56 kJ     (endothermic)

Entropy Change

[1ΔSf(NaBr (aq)) + 1ΔSf(NH3 (g)) + 1ΔSf(H2O (ℓ))] - [1ΔSf(NaOH (aq)) + 1ΔSf(NH4Br (aq))]
[1(141.42) + 1(192.34) + 1(69.91)] - [1(48.25) + 1(195.81)] = 159.61 J/K
159.61 J/K     (increase in entropy)

Free Energy of Reaction (at 298.15 K)

From ΔGf° values:
[1ΔGf(NaBr (aq)) + 1ΔGf(NH3 (g)) + 1ΔGf(H2O (ℓ))] - [1ΔGf(NaOH (aq)) + 1ΔGf(NH4Br (aq))]
[1(-365.87) + 1(-16.48) + 1(-237.18)] - [1(-419.18) + 1(-183.34)] = -17.01 kJ
-17.01 kJ     (spontaneous)

From ΔG = ΔH - TΔS:
-17.03 kJ     (spontaneous)

Equilibrium Constant, K (at 298.15 K)

955.40803194
This process is favorable at 25°C.

Reference(s):

Ebbing, Darrell D. General Chemistry 3rd ed.; Houghton Mifflin Company: Boston, MA, 1990; p 98.

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