For the reaction 3H₂(g) + N₂(g) $\leftrightharpoons$ 2NH₃(g), K_c = 9.0 at 350^$\circ$C. Calculate $\Delta$G^$\circ$ at 350^$\circ$C. A) 25.4 kJ/mol B) 27.4 kJ/mol C) 29.4 kJ/mol D) 31.4 kJ/mol E) None of the above

Question

Quizplus · Accepted Answer

The first step is to write the balanced equation for the reaction:

3H2S(g) + NS2(g) ⇌ 2NHS(g)

Next, we can use the van't Hoff equation to calculate ΔH°:

ln(K2/K1) = -ΔH°/R * (1/T2 - 1/T1)

where K1 and K2 are the equilibrium constants at temperatures T1 and T2, respectively, R is the gas constant (8.314 J/mol·K), and ln denotes the natural logarithm.

Plugging in the numbers, we get:

ln(9.0/1) = -ΔH°/R * (1/623 K - 1/523 K)

Solving for ΔH°, we get:

ΔH° = -(ln(9.0/1) * R * (1/623 K - 1/523 K))

ΔH° ≈ -29.4 kJ/mol

Therefore, the answer is (C) 29.4 kJ/mol.

For the Reaction 3H2(g) + N2(g) ⇋\leftrightharpoons⇋ 2NH3(g), Kc = 9 ∘\circ∘

For the Reaction 3H₂(g) + N₂(g) $\leftrightharpoons$ 2NH₃(g), K_c = 9 $\circ$