Looking for classes? Ksquare Career Institute, Bengaluru →
Thermodynamics
Gibbs Energy Change
1 question from 1 paper, each with its answer.
- question
- 1
- paper
- 1
- of Thermodynamics
- 1.22%
Concepts tested
- Gibbs-Helmholtz equation
All Questions
2004 AIPMT 1 question
-
Standard enthalpy and standard entropy changes for the oxidation of ammonia at 298 K are –382.64 kJ mol$^{-1}$ and –145.6 J K$^{-1}$ mol$^{-1}$, respectively. Standard Gibbs energy change for the same reaction at 298 K is :-$\Delta G^\circ = \Delta H^\circ - T\Delta S^\circ$
Convert $\Delta S^\circ$ to kJ: $-145.6$ J K$^{-1}$ mol$^{-1}$ $= -0.1456$ kJ K$^{-1}$ mol$^{-1}$
$T\Delta S^\circ = 298 \times (-0.1456) = -43.39$ kJ mol$^{-1}$
$\Delta G^\circ = -382.64 - (-43.39) = -382.64 + 43.39$
$\Delta G^\circ = -339.25 \approx -339.3$ kJ mol$^{-1}$