Atomic Structure: A Historical Journey Through Atomic Models

Atomic Structure Development Understanding About Atomic Structure Every material in natural universe This arranged on particles Which very small Which by para expert known with Name atom. Since formerly time First man think about substance compiler every material, Then he formulated theory atom And until Now in era Which all round advanced This, existence atom Already accepted all person, but How form Actually atom It and its composition are not yet known for certain. Experts only they are based on laboratory observations of the symptoms occurs if a material is given a certain treatment. From observation these symptoms, experts then created theories about atoms and estimate form atom the Which known with designation model atom . Atomic models Which proposed by para expert experience development until Now And will Keep going develop along with the more sophisticated instrument laboratory Which supported by progress science and technology Which outside normal. 1. Dalton's Atomic Model John Dalton is a Teacher And expert chemistry ber- British nationality (1776 – 1844). Donations Dalton is uniqueness from the theory Which covers two matter:  He is person First Which involve chemical events as well as events physics in formulating his ideas about pliers atom.  He based his assumptions on quantitative data, not using observation qualitative or luck. Theory atom Dalton stated based on two law, that is law eternity mass And law comparison fixed . Theory atom Dalton developed during the period 1803-1808 and is based on three assumptions tree, that is:  Every element chemistry arranged by particles small Which No can destroyed and separated the so-called atom . While experiencing change chemistry, atom No Can created And annihilated.  All atoms of an element have the same mass and properties, but atoms from something element different with atoms from element Which other, Good mass nor its properties Which different.  In compound chemical, atoms from element Which different do bond with comparison number simple. 2. Thomson's Atomic Model On year 1897 J. J. Thompson found electrons. Based on the munya the, Then Thompson proposed a new known atomic theory with designation model atom Thompson. Model atom Thompson analogized like A bread raisins, in where atom consists on positively charged matter and within it spread electron like raisins in bread raisins. Because of positive and negative charges mixed together with the same amount the same, then whole atom according to Thompson nature neutral (Martin S. Silberberg, 2000). 3. Model Atom Rutherford Antoine Henry Becquerel (1852-1908), a scientist from France in 1896 discovered that uranium and its compounds spontaneously emits particles. Emitted particles It has an electrical charge and has the same properties as light cathode or electron. The elements that emit light are called radioactive elements , And ray Which emitted Also named ray radioactive . There is three type ray radioactive, that is: o ray Which charged positive o ray beta Which charged negative o ray Which No charged