Search results
Results From The WOW.Com Content Network
Sir Joseph John Thomson (18 December 1856 – 30 August 1940) was an English physicist who received the Nobel Prize in Physics in 1906 for his discovery of the electron, the first subatomic particle to be found.
May 6 – John Jacob Abel announces the successful isolation of epinephrine in a paper read before the Association of American Physicians. [7]August 10 – History of aspirin: At the German Bayer chemical and dyestuffs company, pharmacist Felix Hoffmann successfully synthesizes acetylsalicylic acid, a synthetically altered version of salicin, as a less-irritating replacement for standard ...
Discovery of the ultraviolet radiation below 200 nm, named vacuum ultraviolet (later identified as photons) because it is strongly absorbed by air, by the German physicist Victor Schumann [2] 1895 X-ray produced by Wilhelm Röntgen (later identified as photons) [3] 1897 Electron discovered by J. J. Thomson [4] 1899
1897 J. J. Thomson discovered the electron; 1897 Emil Wiechert, Walter Kaufmann and J.J. Thomson discover the electron; 1898 Marie and Pierre Curie discovered the existence of the radioactive elements radium and polonium in their research of pitchblende; 1898 William Ramsay and Morris Travers discover neon, and negatively charged beta particles
1897: J.J. Thomson discovers the electron in cathode rays; 1898: Martinus Beijerinck: concluded that a virus is infectious—replicating in the host—and thus not a mere toxin, and gave it the name "virus" 1898: J.J. Thomson proposed the plum pudding model of an atom; 1898: Marie Curie discovered radium and polonium
An atom with seven electrons arranged in a pentagonal dipyramid, as imagined by Thomson in 1905. The plum pudding model is an obsolete scientific model of the atom.It was first proposed by J. J. Thomson in 1904 following his discovery of the electron in 1897, and was rendered obsolete by Ernest Rutherford's discovery of the atomic nucleus in 1911.
A 1905 diagram by J. J. Thomson illustrating his hypothesized arrangements of electrons in an atom, ranging from one to eight electrons. The arrangement of seven electrons in a pentagonal dipyramid. Atoms were thought to be the smallest possible division of matter until 1899 when J. J. Thomson discovered the electron through his work on cathode ...
[34]: 364 [5] In the same year Emil Wiechert and Walter Kaufmann also calculated the e/m ratio but did not take the step of interpreting their results as showing a new particle, while J. J. Thomson would subsequently in 1899 give estimates for the electron charge and mass as well: e ~ 6.8 × 10 −10 esu and m ~ 3 × 10 −26 g [44] [45]