Question

For the reaction

2C₂H₆(g) + 7O₂(g) ----> 4CO₂(g) + 6H₂O(g)

ΔH° = -2855.4 kJ and ΔS° = 92.7 J/K

The maximum amount of work that could be done when 2.39 moles of C₂H₆(g) react at 349 K, 1 atm is ____ kJ.

Assume that ΔH° and ΔS° are independent of temperature.

Answer 1

2C₂H₆(g) + 7O₂(g) ---------> 4CO₂(g) + 6H₂O(g)

ΔH° = -2855.4 kJ

ΔS° = 92.7 J/K

ΔGo = ΔHo - T ΔSo

       = - 2855.4 - 349 x 0.0927

      = - 2887.75 kJ

2 mol C2H6 -----------> - 2887.75 kJ

2.39 mol C2H6 ------------->   ??

maximum amount of work = 2.39 x - 2887.7 / 2

                                          = - 3450.86

maximum amount of work = - 3.45 x 10^3 kJ