Essay Question #1 Jonathan Slonaker Chemistry 1st Period
John Dalton- The English teacher, chemist, and physicist John Dalton, b. Sept. 6, 1766, d. July 27, 1844, is best known for developing the concept of atoms into a scientific theory that has become a foundation of modern chemistry. Dalton's atomic theory provided a model from which definite predictions of atoms could be made. each atom has a characteristic mass and that atoms of elements are unchanged in chemical processes.
J.J. Thomson- Sir Joseph John Thomson, b. Dec. 18, 1856, d. Aug. 30, 1940, is universally recognized as the British scientist who discovered and identified the electron. Thomson demonstrated that cathode rays were actually units of electrical current made up of negatively charged particles of subatomic size. He came up with a theory that negative particles were embeded into a positive mass. He won the Nobel Prize for physics; in 1908 he was knighted.
Ernest Rutherford-Sir Ernest Rutherford, b. near Nelson, New Zealand, Aug. 30, 1871, d. Oct. 19, 1937 formed modern-day views concerning the nature of matter. Rutherford made his greatest discovery; the structure of the atom. A very small, tightly packed, charged nucleus sprinkled with opposite charges in the mostly empty surrounding void.
Werner Heisenberg-German theoretical physicist Werner Karl Heisenberg, b. Dec. 5, 1901, d. Feb. 1, 1976, was one of the leading scientists of the 20th century. He did important work in nuclear and particle physics, but his most significant contribution was to the development of quantum mechanics. He is best known for his uncertainty principle, which restricts the accuracy with which some properties of atoms and particles--such as position and linear momentum--can be determined simultaneously.
Erwin Schrodinger-The Austrian theoretical physicist Erwin Schrodinger, b. Aug. 12, 1887, d. Jan. 4, 1961, was founder of the wave equation. His studies of the application and statistical interpretation of wave mechanics, the mathematical character of the new statistics, and the relationship of these statistics to statistical thermodynamics earned him fame in the scientific community. He also worked on problems of general relativity and cosmology and on a unified field theory. Late in his life Schrodinger studied the foundations of physics and their implications for philosophy.
Wolfgang Pauli-The Austrian theoretical physicist Wolfgang Ernst Pauli, b. Apr. 25, 1900, d. Dec. 15, 1958, was one of the founders of modern physics. He is most famous for his "Pauli exclusion principle," which states that no two electrons in an atom can have the same four quantum numbers.
James Chadwick-The English physicist James Chadwick, b. Oct. 20, 1891, d. July 24, 1974, is known for his discovery of the neutron. His experiments on the bombardment of certain light elements with alpha particles led to the discovery of the neutron.
Gilbert Lewis-The American chemist Gilbert Newton Lewis, b. West Newton, Mass., Oct. 25, 1875, d. Mar. 23, 1946, contributed to the study of thermodynamics, atomic structure, and bonding, as well as to the theory of acids and bases and the teaching of thermodynamics. Lewis's work in thermodynamics led him to confirm H. Walther Nernst's third law of thermodynamics. His atomic model, known as the Lewis-Langmuir octet, and his distinction between ionic and covalent bonds marked great progress in understanding chemical bonding. His acid-base concept, which asserted that a base donates an electron pair and an acid accepts the pair in covalent bonding, superseded the Bronsted-Lowry theory.
Linus Pauling-The American physical chemist Linus Carl Pauling, b. Portland, Oregon, Feb. 28, 1901, has made extensive contributions to structural chemistry and molecular biology.In the early 1950s he proposed the alpha helix as the basic structure of proteins and narrowly missed discovering the double-helix structure of DNA.