Principles of Modern Chemistry
The current model of atomic structure is the quantum mechanical model. Traditional chemistry starts with the study of elementary particles, atoms, molecules, substances, metals, crystals and other aggregates of matter. This matter can be studied in solid, liquid, or gas states, in isolation or in combination. The interactions, reactions and transformations that are studied in chemistry are usually the result of interactions between atoms, leading to rearrangements of the chemical bonds which hold atoms together. Such behaviors are studied in a chemistry laboratory.
The chemistry laboratory stereotypically uses various forms of laboratory glassware, but glassware is not central to chemistry, and a great deal of experimental (as well as applied/industrial chemistry) is done without it.
A chemical reaction is a transformation of some substances into one or more different substances. The basis of such a chemical transformation is the rearrangement of electrons in the chemical bonds between atoms. It can be symbolically depicted through a chemical equation, which usually involves atoms as subjects. The number of atoms on the left and the right in the equation for a chemical transformation is equal (when unequal, the transformation by definition is not chemical, but rather a nuclear reaction or radioactive decay). The type of chemical reactions a substance may undergo and the energy changes that may accompany it are constrained by certain basic rules, known as chemical laws.
Energy and entropy considerations are invariably important in almost all chemical studies. Chemical substances are classified in terms of their structure, phase, as well as their chemical compositions. They can be analyzed using the tools of chemical analysis, e.g. spectroscopy and chromatography. Scientists engaged in chemical research are known as chemists. Most chemists specialize in one or more sub-disciplines. Several concepts are essential for the study of chemistry; some of them are:
Read more about this topic: Chemistry
Famous quotes containing the words principles of modern, modern chemistry, principles of, principles, modern and/or chemistry:
“Indigenous to Minnesota, and almost completely ignored by its people, are the stark, unornamented, functional clusters of concrete—Minnesota’s grain elevators. These may be said to express unconsciously all the principles of modernism, being built for use only, with little regard for the tenets of esthetic design.”
—Federal Writers’ Project Of The Wor, U.S. public relief program (1935-1943)
“It is beyond a doubt that during the sixteenth century, and the years immediately preceding and following it, poisoning had been brought to a pitch of perfection which remains unknown to modern chemistry, but which is indisputably proved by history. Italy, the cradle of modern science, was at that time, the inventor and mistress of these secrets, many of which are lost.”
—Honoré De Balzac (1799–1850)
“In her present ignorance, woman’s religion, instead of making her noble and free, by the wrong application of great principles of right and justice, has made her bondage but more certain and lasting, her degradation more hopeless and complete.”
—Elizabeth Cady Stanton (1815–1902)
“Unless democracy is to commit suicide by consenting to its own destruction, it will have to find some formidable answer to those who come to it saying: “I demand from you in the name of your principles the rights which I shall deny to you later in the name of my principles.””
—Walter Lippmann (1889–1974)
“He was naturally so sensitive, and so kind. But he had the insidious modern disease of tolerance. He must tolerate everything, even a thing that revolted him.”
—D.H. (David Herbert)
“Science with its retorts would have put me to sleep; it was the opportunity to be ignorant that I improved. It suggested to me that there was something to be seen if one had eyes. It made a believer of me more than before. I believed that the woods were not tenantless, but choke-full of honest spirits as good as myself any day,—not an empty chamber, in which chemistry was left to work alone, but an inhabited house,—and for a few moments I enjoyed fellowship with them.”
—Henry David Thoreau (1817–1862)