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Calculation of standard reaction internal energy, standard reaction of entropy, standard reaction Gibbs energy

Assuming ideal gas behaviour for the reaction:

N2(g) + 3H2(g) -> 2NH3(g)


(i) the standard reaction internal energy (or standard internal energy change of reaction), ΔU, at 298k.

(ii) the standard reaction entropy,ΔS, at 298k.

(iii) the standard reacion Gibbs energy, ΔG, at 350k.

Use the following thermodynamic data for the gases.

The standard enthalpy of formation, ΔH, of NH3(g) and the standard Gibbs energy of formation, ΔG of NH3(g) are 294.1 kJmol-1 and 328.1 kJmol-1, respectively, both at 298k. The heat capacity at constant pressure, Cp, assumed to be independent of the temperature, is given below:

NH3(g). Cp = 98.9JK-1mol-1

N2(g). Cp = 29.1JK-1mol-1

H2(g). Cp = 28.8JK-1mol-1


Thanks for any advice regarding the answer for (i), (ii), (iii)