Calculate Δ_rG at 298 K under the conditions shown below for the following reaction: SO₃(g) + H₂O(g) → H₂SO₄(l) Δ_rG°= -90.5 kJ mol^-1
P(SO₃) = 0.20 atm, P(H₂O) = 0.88 atm

Question

Calculate Δ_rG at 298 K under the conditions shown below for the following reaction: SO₃(g) + H₂O(g) → H₂SO₄(l) Δ_rG°= -90.5 kJ mol^-1 P(SO₃) = 0.20 atm, P(H₂O) = 0.88 atm

Quizplus · Accepted Answer

To calculate the change in Gibbs free energy, we can use the equation:

ΔG = ΔH - TΔS

where ΔH is the change in enthalpy and ΔS is the change in entropy.

ΔH can be calculated using the enthalpies of formation of the reactants and products:

ΔH = ΣnΔHf(products) - ΣnΔHf(reactants)

ΔH = [ΔHf(H2SO4(l)) + ΔHf(SO2(g))] - [ΔHf(SO3(g)) + ΔHf(H2O(l))]

ΔH = [(0 + (-300.4))] - [(-396.2 + (-285.8))]

ΔH = -90.4 kJ/mol

ΔS can be calculated using the standard molar entropies of the reactants and products:

ΔS = ΣnS(products) - ΣnS(reactants)

ΔS = [S(H2SO4(l)) + S(SO2(g))] - [S(SO3(g)) + S(H2O(l))]

ΔS = [(156.9 + 248.2)] - [(256.8 + 69.9)]

ΔS = + 78.4 J/mol/K

We need to convert ΔS to kJ/mol/K:

ΔS = 0.0784 kJ/mol/K

Now we can calculate ΔG using the equation:

ΔG = ΔH - TΔS

ΔG = -90.4 - (298)(0.0784)

ΔG = -86.2 kJ/mol

Therefore, the best choice is D.

Calculate ΔrG at 298 K Under the Conditions Shown Below

Calculate Δ_rG at 298 K Under the Conditions Shown Below