About Me

Foto saya
makassar, sulawesi selatan, Indonesia

Search

Selasa, 16 Maret 2010

WHAT IS PHYSICAL HEMISTRY

Physical chemistry is an empirical science. A science is a set of constructs, called theories, that link fragments of experience into a consistent description of natural phenomena. The adjective “empirical” refers to the common experiences from which the theories grow, that is, to experiments. Simple working hypotheses are guessed by imaginative insight or intuition or luck, usually from a study of experiments. This repetitive interplay in time leads to the formulation of theories that correlate the accumulated experimental information and that can predict new phenomena with accuracy. (Berry, Rice and Ross)

Traditionally, there are three principal areas of physical chemistry: thermodynamics (which concerns the energetics of chemical reactions), quantum chemistry (which concerns the structures of molecules), and chemical kinetics (which concerns the rates of chemical reactions). (McQuarrie and Simon)

Physical chemistry is the branch of chemistry that establishes and develops the principles of the subject. Its concepts are used to explain and interpret observations on the physical and chemical properties of matter. Physical chemistry is also essential for developing and interpreting the modern techniques used to determine the structure and properties of matter, such as new synthetic materials and biological membranes. (Atkins)

Physical chemistry is the study of the physical basis of phenomena related to the chemical composition and structure of substances. It has been pursued from two levels, the macroscopic and the molecular. Knowledge in physical chemistry available today provides a rich, comprehensive view of the world of atoms and molecules that connects their nature with macroscopic properties and phenomena of materials and substances. A starting point for an introduction to physical chemistry is the concept of energy levels in atoms and molecules, distributions among these energy levels, and something familiar, temperature. (Dykstra)

Physical chemistry is the study of the underlying physical principles that govern the properties and behavior of chemical systems. (Levine)

Physical chemistry, like a table with four legs, is built upon four major theoretical areas: thermodynamics, kinetics (or, more generally, transport processes), quantum mechanics, and statistical mechanics This is not all of physical chemistry, no more than a table is only legs. Physical chemistry is a widely diverse subject that cannot be summarized adequately in any brief definition, and there are important parts of physical chemistry that do not fit neatly into this quadrivium. (Noggle)

Physical Chemistry is a fascinating field of study. It can reasonably be claimed that many parts of physics and all parts of chemistry are included within physical chemistry and its applications. Furthermore, it is the course in which most chemistry students first have the opportunity to synthesize what they have learned in mathematics, physics, and chemistry courses into a coherent pattern of knowledge. (Mortimer)

We see it as the quantitative interpretation of the macroscopic world in terms of the atomic-molecular world. To achieve this interpretation, we must organize our observations of macroscopic phenomena, as we do in thermodynamics and in parts of kinetics. We must advance our studies of atoms and molecules, as we do, for example, in quantum mechanics and spectroscopy. Then we must bring these studies together. This coming together is woven into much of the fabric of a modern physical chemistry course. (Barrow)

Physical chemistry is the application of the methods of physics to chemical problems. It includes the qualitative and quantitative study, both experimental and theoretical, of the general principles determining the behavior of matter, particularly the transformation of one substance into another. Although the physical chemist uses many of the methods of the physicist, he applies them to chemical structures and chemical processes. Physical chemistry is not so much concerned with the description of chemical substances and their reactions-this is the concern of organic and inorganic chemistry-as with theoretical principles and with quantitative problems. (Laidler & Meiser)

It is said that there are more than four million chemical compounds. If you add to this list composite materials like alloys and minerals and intermediate species like the free radicals, it becomes truly staggering. The list of properties that interest scientists, even though modest compared to the above list, is also vast. The fascinating aspect of science is that only a few principles are needed to understand the behavior of the huge number of substances and their properties. Physical chemistry is the study of these principles. (Vemulapalli)

FROM http://www.depauw.edu/acad/chemistry/bgourley/Reseach/what_is_physical_chemistry.htm

Tidak ada komentar:

Posting Komentar

Ada kesalahan di dalam gadget ini