composeELEMENT of ATOMS (cannot be divided into smaller particles) DALTON’S MODEL OF AN ATOM: (billiard ball model) Atoms of the same Atoms cannot be elements = same in destroyed Small or Combination of atoms of all their properties changed into atoms two or more elements such as atomic ♥Hard Sphere of any kind by forms a compound. masses chemical reactions. ♥Indivisible
NIELS BOHR MODEL OF AN ATOM:A small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus — similar in structure to the solar system,but with electrostatic forces providing attraction, rather than gravity.
THOMSONS’S MODEL OF AN ATOM: (plum pudding model) ♥ Composed of electrons ♥ Surrounded by a cloud of positive charge to balance the electrons negative charge, like plums surrounded by pudding. ♥ Electrons positioned throughout the atom, but with many structures possible for positioning multiple electrons.♥ Electrons were free to rotate within the cloud of positive substance
APPROXIMATELY Greek philosophers Leucippus and500 BC Democritus proposed that all matter was composed of small indivisible particles called atoms Provided John Dalton proposed1803 AD the Billiard Ball Model basic characteristics of an atom J.J Thomson1897 AD Discovered existence of electrons and its proposed the presence in atoms Plum Pudding Model Albert Einstein1905 AD showed that the frequency of light was proportional to the energy Later led to the equation of E=MC2
Ernest Rutherford Provided information of1909 AD proposed the Solar System Model the existence of a nucleus in an atom Ernest Rutherford Provided a number of1911 AD proposed the Rutherford Model with reference to a previous model by Hantaro Nagaoka essential modern features including the nucleus Niels Bohr1913 AD Provided a more introduced the Bohr Model, accurate model of an which was the expansion of the atom work of Henry Moseley Led to the current Erwin Schrödinger1925 AD proposed the Schrödinger equation atomic orbital models: Quantum Mechanic model / Electron Cloud model
♥Dalton’s Atom Model :http://www.juliantrubin.com/imagesc/dalton1.gifhttp://en.wikipedia.org/wiki/John_Daltonhttp://dl.clackamas.edu/ch104-04/daltons.htm♥Thomson’s Atom Model:♥http://en.wikipedia.org/wiki/Plum_pudding_model♥http://upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Plum_pudding_atom.svg/348px-Plum_pudding_atom.svg.png♥http://www.marcdatabase.com/~lemur/lemur.com/gallery-of-antiquarian-technology/worthies/dalton-1200-scale1000.jpg♥http://en.wikipedia.org/wiki/J._J._Thomson#Other_work♥Bohr’s Atom Model:♥http://cfa-www.harvard.edu/~sasselov/pic/Bohr.jpg♥http://en.wikipedia.org/wiki/Bohr_model♥Rutherford’s Atom Model:♥http://en.wikipedia.org/wiki/Rutherford_model♥Atom Timeline♥http://atomictimeline.net/index.php♥http://www.angelfire.com/mb2/atoms/♥http://www.csmate.colostate.edu/cltw/cohortpages/viney/atomhistory.html♥Dotted Background Pattern:http://3zehn.org♥Other Resources:♥Interactive Science 2 by Tho Lai Hoong and Ho Peck Leng