1 / 26

The Atom

The Atom. I- Theories About the Atom: A- The term Atom comes from the Greek word meaning “ invisible ” or “that which cannot be further cut”. This comes for the Greek thinker Democritus more than 2000 year ago.

jasper-booker
Download Presentation

The Atom

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. TheAtom I-Theories About the Atom:A-The term Atom comes from the Greek word meaning “invisible” or “that which cannot be further cut”. This comes for the Greek thinker Democritus more than 2000 year ago.

  2. 1-The Greeks believed that all matter was made up four basic elements Air Fire Water Earth

  3. B-Dalton’sModel: in the early 1800’ John Dalton said the atom was a solid particle that could not be divided, and each element had its own kind of atom.

  4. C-Thomson’sModel: in 1897 J.J. Thomson discovered that the atom was made up of smaller particle. Thomson discovered the electron. 1- The atom was known to be neutral. The atom must also have a positive charged particle.

  5. a- Thomson never discovered the positive particle but he knew it existed. b- His model known as “PlumPudding”

  6. D-Rutherford’sModel: In 1908, Ernest Rutherford fired a stream of tiny positively charged particle at a very thin sheet of gold foil. He discovered the Nucleus of the atom and found that it contained what Thomson was looking for the positively charged particle the Proton.

  7. 1-Ruther Model is known as “The Solar system”.

  8. E-Bohr Model: In 1913 Niel Bohr said that the electrons move in a definiteorbit around the nucleus known as. 1-EnergyLevel: is the path an electron takes around the nucleus of the atom, it related to the amount of energy it has.

  9. 2-ElectronsEnergies: By heating up or passing electricity through the atom you can increase its energy. a-If the atom gains enough energy the electron can jump to a higher energy level called an ExcitedState. b-To return to it’s original state the atom releases the extra energy in the form of a PHOTON.

  10. c-Spectrum is the finger print of an element each element has its own spectrum.

  11. F-Chadwick’sModel: In 1932 Chadwick discovered a particle in the nucleus of the atom. The Neutron has NOCHARGE but has more mass than the proton. This completed the model of the atom.

  12. Neutron Electron Proton

  13. 1-Today: the atom is described as a central mass surrounded by an electroncloud.

  14. II- HowAtomsDiffer A- All atoms of an element have the same number of protons. The number of protons determines what the element is. 1- AtomicNumber is the number of protons of an atom.

  15. 2- MassNumber: is the total number of Protons and Neutrons in an atom. a- To find the number of neutrons in an atom all you do is subtract the atomicnumber from the massnumber.

  16. Mass Number

  17. B-Isotopes: Atoms of the same element with the same atomic number but a different number of neutrons.

  18. III-ClassifyingElements: A-ThePeriodicTable: Was created by Mendeleev, he put the elements with the same characteristics into columns. 1-The elements line up in increasingatomic numbers.

  19. B- ArrangementofTable: 1-Each row is called a period and each column is called a group. 2-If you know something about an element in a group you know something about them all.

  20. 3-Each box has an element’s symbol, name, atomicnumber,massnumber, and the number of electrons in each energy level.

  21. Atomic Number Number of electrons in each energy level 13 2 8 3 Al Symbol Aluminum Name 26.98 Average atomic mass

More Related