Consider the combustion of solid sulfur to form sulfur dioxide

CHEMISTRY · Multi-part · A Level · Chemistry · Thermodynamics · Thermodynamics

Problem

Consider the combustion of solid sulfur to form sulfur dioxide.

\mathrm{S}_8(s) + 8\,\mathrm{O}_2(g) \to 8\,\mathrm{SO}_2(g)

Thermodynamic data (per mole of reaction as written):

\Delta H^\circ = -2376\,\text{kJ}

\Delta S^\circ = +550\,\text{J}\,\text{K}^{-1}

. The uncatalyzed reaction has an activation energy

E_a = 180\,\text{kJ}\,\text{mol}^{-1}

. (a) Calculate

\Delta G^\circ

for the reaction at

298\,\text{K}

. (b) Calculate

\Delta G^\circ

for the reaction at

800\,\text{K}

. (c) Using your answers from parts (a) and (b), discuss the change in thermodynamic favorability as temperature increases. (d) For each temperature (

298\,\text{K}

and

800\,\text{K}

), evaluate whether the reaction is likely to proceed at a measurable rate in the absence of a catalyst. Support your answer by referencing both

\Delta G^\circ

and

E_a

Related theory

Browse the problem library