ABSTRACT
State functions derive their name from the property that they only depend on the current state of a system. The physical state of matter is described by a number of parameters, termed state variables. The internal energy of a system decreases if the system performs work and/or transfers heat to its surroundings. In biochemistry, reactions typically occur at isothermal and isobaric conditions, nevertheless we find many reaction cycles that bear resemblance to the Carnot cycle. The transport cycle is similar to a reverse Carnot cycle: the transporter takes up cargo from a low concentration side, which corresponds to the process of taking up heat from a cold reservoir. The chemical potential is a driving force for processes and chemical reactions. The chemical potential provides a convenient way to quantify the contribution of each component of the mixture to the free energy. Dialysis is used for buffer exchange of protein solutions.
