ABSTRACT
This chapter introduces the first law of thermodynamics, re-enforcing the differences between path and state functions, and highlights the use of simple state functions to calculate thermodynamic changes along complicated paths. With the subsequent understanding of atomic and molecular structures, developments in the thermodynamics of machines were adapted to describe the thermodynamic properties of materials and chemical reactions. Equilibrium thermodynamics is remarkable in that it captures the bulk behavior of materials and reactions that depend on these incredibly detailed underlying dynamics. Within the field of thermodynamics, an important distinction can be made between "classical" and "statistical" approaches. The chapter concludes with a discussion of the van der Waals gas, to provide a picture of nonideality and its origins. The conservation statement applies when the chapter considers the system and the surroundings together: any change in the internal energy of the system will be matched by an equal and opposite change in the energy of the surroundings.
