Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Matter wave wikipedia , lookup
Elementary particle wikipedia , lookup
Chemical bond wikipedia , lookup
Geiger–Marsden experiment wikipedia , lookup
Wave–particle duality wikipedia , lookup
Hydrogen atom wikipedia , lookup
Atomic orbital wikipedia , lookup
Electron configuration wikipedia , lookup
Atom Models Timeline To help you piece together the story of what we know about the "atom", you will be creating a timeline depicting the development of the scientific model of the atom. It has been through new discoveries by philosophers and scientists in chemistry, as well as physics, that the model of the atom has expanded and changed over time. Your assignment is to research the major contributors and significant discoveries that have impacted the atomic model and, from this material, develop a timeline. Requirements: Your timeline MUST: 1. Match each of the 12 scientists and/or philosophers located in the tables below to key dates and also their contributions to the atomic model. 2. Include pictures of atomic models at their respective year of discovery. Be sure to clearly label key characteristics of these models (protons, neutrons, electrons, nucleus, etc…): indivisible, solid sphere model quantum mechanical model nuclear or planetary model plum (raisin) pudding model orbit or Bohr model 3. Be chronological in its sequence, with the dates clearly shown (it need not be to scale), and at a minimum include the information contained in the following tables. 4. Be neat and legible. Deadlines and Guidelines: Your timeline is due on ____________________. 15 points will be deducted for every day that it is late. Extra credit may be given for the inclusion of other atomic scientists and/or philosophers. Additional scientists and/or philosophers that may be included are Wolfgang Pauli, Leucippus of Miletus, Henri Becquerel, Francis Aston, and Amadeo Avogadro. All required information for the original group of atomic scientists and/or philosophers should be included. A maximum of 5 additional scientists may be included for extra credit. 3 extra credit points will be awarded at for each additional scientist listed with their major contribution and date of discovery. I strongly recommend using the websites listed below to identify key dates, as different sources may have slightly different dates. To help you with your timeline, mark the number of the scientist next to his corresponding key date and contribution! Key Scientists/Philosophers Key Dates 1. Aristotle ~400 B.C. 2. Niels Bohr mid 300’s B.C. 3. James Chadwick 1803 4. John Dalton 1897 5. Louis deBroglie 1900 6. Democritus of Adbera 1909 7. Werner Heisenberg 1909 8. Robert Millikan 1912 9. Max Planck 1924 10. Ernest Rutherford 1926 11. Erwin Schrödinger 1927 12. Joseph John Thomson 1932 Contributions atom • electrons travel in specified energy levels • spectrum lines produced when electrons move • atomos- indivisible • first to identify possibility of an atom • smallest piece of matter • measured charge of an electron • oil drop experiment • completed with Thomson • “uncertainty principle” • impossible to determine the position and the momentum of a particle at the same time • electrons have properties of both waves and particles • group of waves named after this scientist • showed mathematically that waves can be used to describe electrons in atoms • determined probability location of electrons in atoms • “cloud” model aka quantum mechanical model • Einstein used this scientist’s work to study photons • father of modern atomic theory • 5 parts to theory • includes elements are composed of atoms • also includes element’s atoms are identical in mass • proposed solid sphere model of the atom • discovered electron • described nature of cathode rays • plum pudding model of atom • four “elements”: earth, fire, air, water • believed in reasoning instead of scientific experiments • dismissed Democritus’ atom idea as “worthless” • gold foil experiment • atom has small positive nucleus, remainder is empty space • predicted existence of neutrons • proposed planetary model of atom • helped with the development of the nuclear model • discovered neutron Helpful Websites: http://library.thinkquest.org/19662/low/eng/ancient.html http://www.aip.org/history/electron/jj1897.htm http://regentsprep.org/Regents/physics/phys05/catomodel/ruther.htm http://csep10.phys.utk.edu/astr162/lect/light/bohr.html http://scienceworld.wolfram.com/biography/Dalton.html http://library.thinkquest.org/19662/low/eng/neutrons.html http://www.nobeliefs.com/atom.htm http://www.juliantrubin.com/bigten/millikanoildrop.html http://mhsweb.ci.manchester.ct.us/library/webquests/atomicmodels.htm Rubric for Project Scientists (60 pts): 5 points each for a correctly matched scientist to his correct key date and contribution. Points: Timeline (40 pts) Atomic Models 10 Pictures of all models are present and coupled with their respective dates. Chronological in Sequence Dates and Information (2 pts. for each scientist) 24 All dates, scientists, and contributions are clearly marked on the timeline. 8 Pictures of 4 models are present and coupled with their respective dates. 6 4 2 Pictures of 3 Pictures of 2 Picture of 1 models are models are model is present and present and present and coupled with coupled with coupled with their their its respective respective respective dates. dates. date. Timeline is chronological. 22-16 14-8 6-2 0 Most dates, Some dates, Few dates, No dates, scientists, scientists, scientists, scientists, and and and and contributions contributions contributions contributions are clearly are clearly are clearly are clearly marked on marked on marked on marked on the timeline. the timeline. the timeline. the timeline. Points: TOTAL POINTS: % KEY Key Scientists/Philosophers 1. Aristotle 2. Niels Bohr 3. James Chadwick 4. John Dalton 5. Louis deBroglie 6. Democritus of Adbera 7. Werner Heisenberg 8. Robert Millikan 9. Max Planck 10. Ernest Rutherford 11. Erwin Schrödinger 12. Joseph John Thomson Contributions 2 atom • electrons travel in specified energy levels • spectrum lines produced when electrons move 6 • atomos- indivisible • first to identify possibility of an atom • smallest piece of matter 8 • measured charge of an electron • oil drop experiment • completed with Thomson 7 • “uncertainty principle” • impossible to determine the position and the momentum of a particle at the same time 5 • electrons have properties of both waves and particles • group of waves named after this scientist 11 • showed mathematically that waves can be used to describe electrons in atoms Key Dates 6 - ~400 B.C. 1 - mid 300’s B.C. 4 - 1803 12 - 1897 9 - 1900 10 - 1909 8 - 1909 2 - 1912 5 - 1924 11 - 1926 7 - 1927 3 - 1932 9 • Einstein used this scientist’s work to study photons •4 • father of modern atomic theory • 5 parts to theory • includes elements are composed of atoms • also includes element’s atoms are identical in mass • proposed solid sphere model of the atom •1 2 • discovered electron • described nature of cathode rays • plum pudding model of atom 1 • four “elements”: earth, fire, air, water • believed in reasoning instead of scientific experiments • dismissed Democritus’ atom idea as “worthless” 10 • gold foil experiment • atom has small positive nucleus, remainder is empty space • predicted existence of neutrons • proposed planetary model of atom 3 • helped with the development of the nuclear model • determined probability location of electrons in atoms • “cloud” model aka quantum mechanical model • discovered neutron