Modified thermodynamic square with physical considerations

Abstract

"Modified thermodynamic square is suggested with some physical considerations. The Legendre transformed relations of the internal energy E, the Helmholtz free energy F, the Gibbs free energy G, and the enthalpy H can be represented at the vertices on a diamond diagram, with these vertices being located at the center of the edges of the thermodynamic square. Finally, the complete thermodynamic square can be obtained by marking the state variables at the vertices of the square. The internal energy and the Helmholtz free energy are represented by E and F for mnemonic convenience. Knowing the conjugate relations between the state variables and differentiating between the extensive and the intensive variables can help in remembering and utilizing the diagram. ? 2019 The Korean Physical Society. All rights reserved.