Physical chemistry (also called physicochemistry) is the explanation of macroscopic, microscopic, atomic, subatomic, and particulate phenomena in chemical systems in terms of physical concepts; sometimes using the principles, practices and concepts of physics like thermodynamics, quantum chemistry, statistical mechanics and dynamics.^[1]

Physical chemistry in contrast to chemical physics is still predominantly a macroscopic or supra-molecular science, as the majority of the principles on which physical chemistry was founded are concepts related to the bulk rather than on molecular/atomic structure alone; for example, colloids.^[2], chemical equilibrium etc.

Some of the relationships that physical chemistry has lately tried to resolve include the effects of:

1. Intermolecular forces on the physical properties of materials (plasticity, tensile strength, surface tension in liquids).
2. Reaction kinetics on the rate of a reaction.
3. The identity of ions on the electrical conductivity of materials.

There is a large body of knowledge embodied in this very old branch of chemistry that can not be explained just by using the concepts of physics.

[edit] History

The term "physical chemistry" was probably first introduced by Mikhail Lomonosov in 1752, when he presented a lecture course entitled "A Course in True Physical Chemistry" (Russian: «Курс истинной физической химии») before the students of Petersburg University.

The foundation of modern physical chemistry is thought to have been laid in the 1860s to 1880s by work on chemical thermodynamics, electrolytes in solutions, chemical kinetics and other subjects. One milestone was the publication in 1876 by Josiah Willard Gibbs of his paper, On the Equilibrium of Heterogeneous Substances, which contained several of the cornerstones of physical chemistry, such as Gibbs energy, chemical potentials, Gibbs phase rule ^[3] and subsequent naming and accreditation of enthalpy to Heike Kamerlingh Onnes and to macromolecular processes.^{[citation needed]}

The first scientific journal for publications specifically in the field of physical chemistry was the German journal, Zeitschrift für physikalische Chemie, founded in 1887 by Wilhelm Ostwald and Jacobus Henricus van 't Hoff, which were two of the other leading figures of physical chemistry in the late 19th century and early 20th century together with Svante August Arrhenius. All three were awarded with the Nobel Prize in Chemistry in the period 1901-1909.

Developments 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 into quantum chemistry from the 1930s, where Linus Pauling was one of the leading names. Theoretical developments have gone hand in hand with developments in experimental methods, where the use of different forms of spectroscopy, such as infrared spectroscopy, microwave spectroscopy, EPR spectroscopy and NMR spectroscopy, is probably the most important 20th century development.

Further development in physical chemistry may be attributed to discoveries in nuclear chemistry, especially in isotope separation (before and during WW II), and after, by development of calculation algorithms in field of "additive physicochemical properties" (practically all of physicochemical properties, as: boiling point, critical point, surface tension, vapor pressure etc. - more than 20 in all, can be precisely calculated from chemical structure, even if such chemical molecule is still non existent), and in this area is concentrated practical importance of contemporary physical chemistry. -> see, Group contribution method, Joback method

[edit] Notes

1. ^ Quantum Chemistry (p3 - "PHYSICAL CHEMISTRY"), states that "We can divide physical chemistry into four areas: thermodynamics, quantum chemistry, statistical mechanics and kinetics".
2. ^ Physical Chemistry of Macromolecules (p1 - "INTRODUCTION"), defines the formation of physical chemistry as being between macromolecules and colloids in modern physical chemistry. Also defines the "fierce battles" in the 1900s between the inclusion of colloids AS macromolecules.
3. ^ Josiah Willard Gibbs, 1876, "On the Equilibrium of Heterogeneous Substances", Transactions of the Connecticut Academy of Sciences

[edit] References

1. Levine, I. N. (1978). Physical Chemistry McGraw-Hill publishing ISBN 0-07-037418-X
2. Atkins, P.W. (1978). Physical Chemistry Oxford University Press ISBN 0-7167-3539-X
3. Berry, S. R., Rice, S. A, Ross, J. (2000). Physical Chemistry 2nd ed. Oxford University Press. ISBN 0-19-510589-3
4. Hunter, R. J. (1993) Introduction to Modern Colloid Science Oxford University Press. ISBN 0-19-855386-2
5. Hiemenz, P. C., Rajagopalan, R., (1997). Principles of Colloid and Surface Chemistry Marcel Dekker Inc., New York. ISBN 0-8247-9397-8
6. Moore, W.J. (1963). Physical Chemistry 4th ed. Longman publishers/London/Prentice Hall, NJ.

[edit] See also

Physical chemistry portal

[edit] Sub-topics

• Photochemistry
• Thermochemistry
• Chemical kinetics
• Quantum chemistry
• Electrochemistry
• Surface chemistry
• Solid-state chemistry
• Spectroscopy
• Biophysical chemistry
• Materials science
• Physical organic chemistry
• Membrane formation
• Micromeritics

[edit] Publications

• Important publications in physical chemistry(chemistry),
• Important publications in physical chemistry(physics)