The cubic-plus-chain (CPC) equation of state framework for nonpolar chain molecules hybridizes the classical cubic equation of state with the chain equation of state from SAFT (Sisco and Abutaqiya et al., Ind. Eng. Chem. Res., 2019, 58, 7341). In this framework, the residual Helmholtz energy of the system is given by a monomer and chain contribution. The monomer contribution comes from the classical cubic equation of state, in which repulsive and attractive character is ascribed to the monomer beads, and the chain equation of state bonds the monomer beads to form linear chains. In this work, the general form of CPC is shown, with application to any cubic equation of state and radial distribution function of choice, the shape of the isotherms of the CPC equation of state function is discussed, and a robust numerical algorithm for converging the volume loop is provided.