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William Nicholson (13 December 1753 – 21 May 1815) was an English writer, translator, publisher, scientist, inventor, patent agent and civil engineer. He launched the first monthly scientific journal in Britain, Journal of Natural Philosophy, Chemistry, and the Arts, in 1797, and remained its editor until 1814.
R = radius of the gold atom = 1.44 × 10 −10 m; v = speed of the alpha particle = 1.53 × 10 7 m/s; m = mass of the alpha particle = 6.64 × 10 −27 kg; k = Coulomb constant = 8.987 × 10 9 N·m 2 /C 2; N = number of electrons in the gold atom = 79; gives the average angle by which the alpha particle should be deflected by the atomic ...
This was in a gold atom known to be 10 −10 metres or so in radius—a very surprising finding, as it implied a strong central charge less than 1/3000th of the diameter of the atom. The Rutherford model served to concentrate a great deal of the atom's charge and mass to a very small core, but did not attribute any structure to the remaining ...
Friedrich Wilhelm Ostwald (German: [ˈvɪlhɛlm ˈɔstˌvalt] ⓘ; 2 September [O.S. 21 August] 1853 – 4 April 1932) was a German chemist and philosopher.Ostwald is credited with being one of the founders of the field of physical chemistry, with Jacobus Henricus van 't Hoff, Walther Nernst and Svante Arrhenius. [1]
An image from John Dalton's A New System of Chemical Philosophy, the first modern explanation of atomic theory.. This timeline of chemistry lists important works, discoveries, ideas, inventions, and experiments that significantly changed humanity's understanding of the modern science known as chemistry, defined as the scientific study of the composition of matter and of its interactions.
Devised the torsion balance, by means of which he discovered what is known as Coulomb's law: the force exerted between two small electrified bodies varies inversely as the square of the distance; not as Franz Aepinus in his theory of electricity had assumed, merely inversely as the distance.
The earliest gold artifacts were discovered at the site of Wadi Qana in the Levant. [13] Silver is estimated to have been discovered in Asia Minor shortly after copper and gold. [14] There is evidence that iron was known from before 5000 BC. [15] The oldest known iron objects used by humans are some beads of meteoric iron, made in Egypt in ...
Small amounts of natural gold have been found in Spanish caves used during the late Paleolithic period, around 40,000 BC. [5] The earliest gold metallurgy is known from the Varna culture in Bulgaria, dating from c. 4600 BC. [6] Silver, copper, tin and meteoric iron can also be found native, allowing a limited amount of metalworking in ancient ...