Question

For a given reaction, Δ H = 35.5 kJ mol^-1 and Δ S = 83.6 J K⁻1 mol⁻1. The reaction is spontaneous at

• A. \(T>425\,\text{K}\)
• B. all temperatures
• C. \(T>298\,\text{K}\)
• D. T<425K

Hint:

If Δ H>0 and Δ S>0, spontaneity occurs at high T.

Answer 1

The Correct Option is A

Δ G = Δ H - TΔ S < 0 ⟹ T > (Δ H)/(Δ S) = (35500)/(83.6) ≈ 425K