phase diagram

Introduction: Chemical balance is an important topic in chemistry. In order to express and simulate the balance, the thermodynamic concept of free energy is usually used. In multicomponent systems, Gibbs free energy is a function of pressure, temperature and the amount (mass, mol) of each component. When one of these parameters is changed, the occurrence state is changed to a stronger preferable state. This state has the lowest free energy. When the free energies of all states are equal to each other, the system is in equilibrium.

The state diagram is a graphical representation of chemical equilibrium. Since chemical equilibrium depends on the composition, pressure and temperature of the system, the state diagram should be able to show an equilibrium state of any composition at any temperature and pressure of the system. First of all, after defining some terms we will describe two component state diagrams starting from a simple system and entering a more complex system. System - The system is part of the universe under consideration. Therefore, some systems may or may not have fixed boundaries. For example, if you are testing a beaker containing salt and water and you are interested only in the salt and water contained in the beaker, the system will contain only the salt and water contained in the beaker.

It is necessary to prepare a state diagram for systematic study of microemulsion composition. From this it is possible to determine the extent of the microemulsion region and establish a relationship with other phases. Pseudo-ternary state diagrams can be constructed by titration. As the quaternary phase diagram (four component system) is time consuming and difficult to interpret, each corner of the graph represents 100% of a particular component, a pseudo ternary phase to find a different region containing the microemulsion region A diagram is constructed. The pseudo-ternary phase diagram of oil, water and cosurfactant / surfactant mixture is constructed using fixed co-surfactant / surfactant weight ratio. Weighed in a glass vial in advance and fixed with water droplets, and the phase diagram was obtained by mixing well stirred components at room temperature. Formation of single phase / two phase system was confirmed by visual inspection. (Jha S. K., et al., 2011)