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Models and models for the atom The idea of the atom was a source of conflict for a long time, as some thinkers advocated the indivisibility of the atom, others claimed that matter was infinitely divisible, and still later was also argued that the absence of the atom, as René Descartes(1596-1650 ), in the seventeenth century. The foundations of chemistry were restored in 1807 by English chemist and physicist John Dalton(1766-1844), who proposed a more consistent model for the atom. See his atomic hypothesis: All atoms of a given element are identical. atoms of different elements have different masses. compound A is a specific combination of atoms of more than one element. In a chemical reaction, atoms are not created or destroyed but change partners to produce new substances. Joseph John Thomson(1856-1940), during the investigation of "cathode rays" (rays emitted when it is applied between two electrodes a high voltage), showed that these rays were negatively charged particle beams, coming from the cathode. Regardless of the material of this, the particles were always the same, so he concludes that these were parts of atoms, which he called electrons. For the Thomson model: "Negatively charged electrons would be confined to a continuous distribution of positive charge.was assumed that the shape of the distribution of positive charge was due to the spherical ... mutual repulsion, the electrons would be uniformly distributed in the sphere of positive charge. (EISBERG.; Resnick, 1979, p.123) This model of Thomson became known as "raisin pudding", but was replaced when hisformer student Ernest Rutherford(1871-1937), experimentally showed that the positive charge is concentrated in a region, the core, the center of the atom . Rutherfod to the model of atomic structure, all of this positive charge atom, and hence its entire mass is concentrated in a small alleged center region called the nucleus. (EISBERG.; Resnick, 1979, p.127)
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Modeli i modeli za atom Ideja atoma je izvor sukoba i za dulje vrijeme, kao što neki mislioci zagovarao nedjeljivost atoma, drugi tvrdili da je stvar bila beskrajno djeljiva, te se kasnije također je tvrdio da je izostanak atoma, kao René Descartes(1596-1650 ), u sedamnaestom stoljeću. Temelji kemije su obnovljena u 1807 od strane engleskog kemičar i fizičar John Dalton(1766-1844), koji je predložio više dosljedan model atoma. Vidi mu atomsku hipotezu: Svi atomi određenog elementa su identični. Atomi različitih elemenata imaju različite mase. Spoj je specifična kombinacija atoma više od jednog elementa. U kemijskoj reakciji, Atomi nisu stvorena ili uništena, ali promijeniti partnere za proizvodnju nove tvari (Atkins, JONES, 1999, Joseph John Thomson(1856-1940), tijekom istrage "katodnih zraka" (zrake emitiraju kada se primjenjuje između dvije elektrode visokog napona), pokazalo je da su te zrake su negativno nabijena čestica grede, dolazi iz katode. Bez obzira na materijal od ove, čestice su uvijek isti, pa je zaključio da su to dijelovi atoma, koje je pozivao elektroni. Za Thomson modela: "Negativno nabijenih elektrona će biti ograničena na kontinuiranom distribucijom pozitivnog naboja.Pretpostavlja se da je oblik raspodjele pozitivnog naboja je zbog sferne ... međusobne odbojnosti, elektroni bi se ravnomjerno raspoređena u sferu pozitivnog naboja." (EISBERG.; Resnick, 1979, p.123) Ovaj model Thomsona je postao poznat kao "grožđica puding", ali je zamijenjen kada je njegovbivši student Ernest Rutherford(1871-1937) Eksperimentalno su pokazali da je pozitivan naboj je koncentriran u regiji, srž, središte atoma . Rutherfod na modelu atomske strukture, sve ove pozitivnog naboja atoma, a time i cjelokupna masa koncentrirana u malom navodnog centar regije zove jezgru (EISBERG.; Resnick, 1979,p.127).