Physical chemistry is the study of macroscopic, atomic, subatomic and particle phenomena in chemical systems in terms of principles, practices and concepts of physics such as movement, energy, force, time, thermodynamics, chemistry Quantum mechanics, statistical mechanics, analytical dynamics and chemistry. balance.
Physical chemistry, in contrast to chemical physics, is predominantly (but not always) a macroscopic or supra-molecular science, since most of the principles on which it was founded are related to mass and not just to molecular structure / Atomic, chemical equilibrium and colloids).
Some of the relationships that physical chemistry strives to solve include the effects of:
1. Intermolecular forces acting on the physical properties of the materials (plasticity, tensile strength, surface tension in liquids).
2. Kinetics of reaction on reaction rate.
3. The identity of the ions and the electrical conductivity of the materials.
4. Surface and electrochemical science of cell membranes.
5. Interaction of one body with another in terms of amounts of heat and work called thermodynamics.
6. Heat transfer between a chemical system and its environment during the phase change or chemical reaction that is carried out called thermochemistry
7. Study of the colligative properties of the number of species present in solution.
8. The number of phases, the number of components and the degree of freedom (or variance) can be correlated with each other using the phase rule.
9. Reactions of electrochemical cells.
The term "physical chemistry" was coined by Mikhail Lomonosov in 1752 when he presented a master course entitled "A Course in True Physics Chemistry" to students at the University of Petersburg. In the preamble to these lectures he gives the definition: "Physical chemistry is the science that must explain under provisions of physical experiments the reason for what is happening in complex bodies through chemical operations."
Modern physical chemistry originated in the 1860s and 1880s with works on chemical thermodynamics, electrolytes in solutions, chemical kinetics and other topics. A landmark was Josiah Willard Gibbs's 1876 publication of his paper on the Balance of Heterogeneous Substances. This article introduced several of the cornerstones of physical chemistry, such as Gibbs energy, chemical potentials, and Gibbs phase rule. Other milestones include the subsequent naming and accreditation of enthalpy to Heike Kamerlingh Onnes and macromolecular processes.
The first scientific journal specifically in the field of physical chemistry was the German magazine Zeitschrift für Physikalische Chemie, founded in 1887 by Wilhelm Ostwald and Jacobus Henricus van 't Hoff. Together with Svante August Arrhenius, these were the leading figures in physical chemistry in the late nineteenth and early twentieth centuries. All three were awarded the Nobel Prize in Chemistry between 1901-1909.
Events in the following decades include the application of statistical mechanics to chemical systems and work on colloids and surface chemistry, where Irving Langmuir made many contributions. Another important step was the development of quantum mechanics in quantum chemistry in the 1930s, where Linus Pauling was one of the main names. The theoretical developments have gone hand in hand with the evolution of experimental methods, where the use of different forms of spectroscopy, such as infrared spectroscopy, microwave spectroscopy, electron para-magnetic resonance and nuclear magnetic resonance spectroscopy is probably the development Most important of the 20th century.
The development of physical chemistry can be attributed to discoveries in nuclear chemistry, especially in the separation of isotopes (before and during World War II), more recent discoveries in astrochemistry, as well as in the development of computational algorithms in the field of "Physicochemical properties, such as boiling point, critical point, surface tension, vapor pressure, etc. - more than 20 in total - can be accurately calculated only from The chemical structure, even if the chemical molecule remains without synthesising) The practical importance of contemporary physical chemistry.