STRUCTURE OF AN ELEMENTS - ATOM

An atom is composed of three different types of particles, proton, neutron and electron. atoms always are neutrally charged, an atom will always have the same number of protons and electrons.   Atoms always have same number of negative and positive charges. hydrogen atom have no neutron.
            Atoms become ions when become charged. This change occurs when atom has lost or gained electrons.
           For (eg) atom the left or or above represents ( Helium) is usually a gas. Lithium has 3 proton, 3 neutron 3 electrons. The proton and neutron from the nucleus and the electrons form a cloud that surrounding the nucleus. It's the number of protons determines kind of element the atom will be. Helium atom always have two protons. It's a non charged atom. This also have two electrons. Hydrogen atom have no neutron.
                 The Lithium and they different in the number of neutrons this is called isotopes. Most of the Lithium that we use that lithium ion battery. Lithium has 6 which has 3 neutrons. There are also small number of Lithium in lithium ion battery as well. Both of these varieties of Lithium are stable. They don't break down. They are not radioactive. 

ATOMIC STRUCTURE :
William Roentgen 1985 the excited the imagination who rushed to study this phenomenon. within a months, Henri found that both uranium metals and its salt of the elements given off a different form of radiation, which would also pass through solids. In 1898,Marie Curie found that compounds of thorium were also "radioactive" Staking efforts she eventually isolated two more radioactive chemical elements (eg) polonium and radium from ores that contained uranium.
      By Rutherford found that were at least two different forms of radioactivity when he studied the absorption of the radioactivity by thin sheets of metal foil. Which he called  (α) particles were absorbed by metal foil was a few hundreds of a centimetre thinner. The other (β) particles would pass through 100 times as much metal foil before they all are become absorbed. Thereafter, a third form of radiation (γ) rays that discovered that would penetrate as much as few many centimetres of lead. The direction in which particles were deflected by electric field suggested that were positively charged. The magnitude of the deflection they has same charge to mass ratio as Helium 2+ ions. Rutherford built an apparatus that allowed - particles to pass through very high thin glass wall into evacuated flask contained a pair of metal electrodes. After some days, he connected this  electrodes to a lithium ion battery and noted that the gas in the flask did indeed give off the magnetic fields, demonstrated that β particles was negatively charged. They had some charge to mass ratio as an electron and no detectable differences have been found between β- particles and electrons. The fact is particles are ejected from the nucleus of an atom when it undergoes radioactive decay. 
        The real fact is that rays always not deflected by electric or magnetic fields and this rays don't carry the electric chare. They travel at the speed of light and they are classified as a form of electromagnetic radiation that carries more energy than X-rays. 
Growth Decay:
Rutherford and Frederick soddy, The radioactive substances became a less active with time. The formation of atoms of a different types of element. 1903's they concluded that radioactivity was accompanied by a change in the structure of the atom. They assumed that radiation was emitted an element decayed into different kinds of atom. 
          1910's totally 40 radioactive elements has been isolated that were associated with the process by uranium metal decayed to lead (Pb) element... This is created problem because there was space for only 11 elements between the (Pb) and uranium. By 1913, Fajans and fredick soddy proposed and explained for this rules based on the following rules below. 
1) The α- decay are emitted when elements is formed that belongs two spaces to the Uranium atom ( atomic number z= 92) for example, emits an α- particles when decay to form the thorium element atom number ( z=92)
2) β ( beta) particles are emitted radiation when an element is formed that belongs one space to another see the periodic table. (Eg) Actinium atomic number z= 89 emits β particles, when it decay form thorium element atomic number z=90. 
The radioactive elements fall the same place in the periodic table and different forms of the same chemical elements. The thorium radioactive are produced by the α - decay of uranium is a different forms of the elements than the radioactive thorium element obtained by the β- decay of Actinium element. 


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