UO2 (s) + 4 HF (aq) → UF4 (s) + 2 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.

UO2            Mass: g
HF             Mass: g  or Solution Volume: mL of Concentration: mol/L
UF4            Mass: g
H2O            Mass: g
Heat Released: kJ

Enthalpy of Reaction

[1ΔHf(UF4 (s)) + 2ΔHf(H2O (ℓ))] - [1ΔHf(UO2 (s)) + 4ΔHf(HF (aq))]
[1(-1853.51) + 2(-285.83)] - [1(-1129.68) + 4(-255.64)] = -272.93 kJ
-272.93 kJ     (exothermic)

Entropy Change

[1ΔSf(UF4 (s)) + 2ΔSf(H2O (ℓ))] - [1ΔSf(UO2 (s)) + 4ΔSf(HF (aq))]
[1(151.04) + 2(69.91)] - [1(77.82) + 4(145.48)] = -368.88 J/K
-368.88 J/K     (decrease in entropy)

Free Energy of Reaction (at 298.15 K)

From ΔGf° values:
[1ΔGf(UF4 (s)) + 2ΔGf(H2O (ℓ))] - [1ΔGf(UO2 (s)) + 4ΔGf(HF (aq))]
[1(-1761.46) + 2(-237.18)] - [1(-1075.29) + 4(-262.34)] = -111.170000000001 kJ
-111.17 kJ     (spontaneous)

From ΔG = ΔH - TΔS:
-162.95 kJ     (spontaneous)

Equilibrium Constant, K (at 298.15 K)

3.0007173129e+019
This process is favorable at 25°C.

Reference(s):

Swaddle, T.W. Inorganic Chemistry; Academic Press: San Diego, 1997; p 230.

Back to list of reactions