Important Discoveries in Chemistry

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Atomic Theory
An important discovery in Chemistry is the Atomic Theory, John Dalton linked invisible atoms. Dalton’s atomic theory was based on the belief that atoms could be dignified by the differences in their masses. He first stated his theory in 1803 at the Royal Institution, the theory had six basic ideas : all matter is composed of atoms, atoms cannot be made or destroyed, all atoms of the same element are identical, and different elements have different types of atoms. Atomic Theory didn’t start with though John Dalton in fact it started with Democritus dating all the way back to about 460 B.C.. He believed that there were small invisible bodies from which everything is made of and travels in a void of space. He also rationalized the different laws of chemical combination during this time. Many, many, many years later in 1704 Newton came along and proposed a mechanical with small solid masses and that forces held atoms together. In 1803 Dalton said that, “All matter is composed of atoms and that they can’t be created nor destroyed, atoms of the same element are identical, chemical reactions can happen when atoms are rearranged and compounds are created from atoms of elements. His theory explained things that were unclear at the time. In 1894 G.J. Stoney put out the idea that electricity was form of electrons. He started the idea of using symbols to represent the elements and he contributed to finding out the exact atomic weight. Later on in 1897 J.J. Thomson used a CRT to experimentally find out the charge of an electron. He did this by multiplying 1.79 by 10 8. In 1900 Planck used the idea of quanta to clarify hot glowing matter. In 1903 Nagaoka suggested a “Saturnian” model of atoms with flat rings of electrons circli...

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...analyze gunpowder residues. Tracers are radioisotopes used in agriculture to test the effects of herbicides, pesticides, and fertilizers on plants. A tracer is introduced into the substance being tested. Devices that detect radioactivity are used to locate the substance being tested. The tracer can be monitored in animals that consume the plants as well as in the water and soil.

Works Cited

W., Isabella. "Timeline of the Atomic Theory." Timetoast. Timetoast, n.d. Web. 06 Nov. 2013. http://www.timetoast.com/timelines/61477
Leon, Pro. N,. "Modern Atomic Theory." Modern Atomic Theory. N.p., n.d. Web. 06 Nov. 2013. http://www.iun.edu/~cpanhd/C101webnotes/modern-atomic-theory/modern-atomic-theory.html "Atomic Theory." Atomic Theory. N.p., n.d. Web. 6 Nov. 2013.
http://curiosity.discovery.com/question/principle-atomic-thoery

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