Across
- 1. Bohr proposed his quantized shell _______ of the atom to explain how electrons can have stable orbits around the nucleus.
- 6. In 1913, Niels Bohr proposed a theory for the hydrogen atom based on _______ that energy is transferred only in certain well defined quantities.(two words)
- 7. Chadwick’s research went to the making of _______ explosions and nuclear energy.
- 10. expanded the atomic theory of____. dividing them; means eternity of existing nature of space and motion; density is proportional to the volume of an atom
- 11. Atoms cannot be_____, created, or destroyed.
- 17. where Democritus lived
- 18. the first possible way to experiment dalton’s theory
- 22. Rutherford designed an experiment to use the alpha particles emitted by a radioactive element as probes to the unseen world of ________.(two words)
- 26. John Dalton Published a book_____(two words)
- 28. Elements are made of extremely small particles called _______.
- 29. Ernest Rutherford discovered that ____ was composed of 2 different kinds of atoms, and proved the existence of isotopes in a stable element.
- 33. all ____ was composed of atoms
- 34. John Dalton Discovered the _____ in 1803
- 36. 1766-1844(two words)
- 39. Bohr’s atomic model was called 3 things, the Rutherford-Bohr model, __________ and the Bohr diagram(two words)
- 40. _____ lived in the time 460-370B.C.
- 41. J.J Thomson demonstrated that cathode rays were ______ charged
- 43. J.J Thomson died in ________ on August 30, 1940
- 44. Ernest Rutherford discovered the atomic ____ and developed a model of the atom that was similar to the solar system.
- 45. J.J. Thomson ______ 13 books and more than 200 papers in his lifetime.
- 46. First person to _____ the atom existed(3words)
Down
- 2. in the span of seven years, he published ___ papers.(8*10=?)
- 3. name of J.J. Thomson’s atomic model(two words)
- 4. Electrons should move around the nucleus but only in prescribed orbits. When jumping from one orbit to another with ______ energy, a light quantum is emitted.
- 5. democritus was called
- 7. This particle in the center that now has a neutral charge became known as the _______.
- 8. all known _______ elements emit 2 kinds of radiation: positively and negatively charged, or alpha and beta.
- 9. If the atom _______ energy, the electron jumped to a level further from the nucleus;if it radiated energy, it fell to a level closer to the nucleus.
- 12. James Chadwick _____ on July 24, 1974
- 13. which scientist contributed greatly to the making of the German atomic program during ww11?(last name only)
- 14. who was born on 1932?
- 15. Atoms of a given element are ____ in size, mass, and other properties
- 16. J.J thomson originally called these particles '______,' although they are now called electrons.
- 19. Ernest Rutherford met ______ (who would soon discover the electron), who encouraged him to study recently-discovered x-rays.(two words)
- 20. What was the name of Rutherford's model called?(3words)
- 21. Chadwick could tell that the radiation was neutral because it was not deflected by electric or _____ fields and it did not invoke the photoelectric effect.
- 23. the atom was believed to be composed of a _______ charged nucleus surrounded by negatively charged electrons.
- 24. Compounds are formed by a _________ of 2 or more different kinds of atoms.
- 25. Heisenberg was Most famous for his ______ ________ and theory of quantum mechanics which he published at the age of twenty-three in 1925. (two words)
- 27. _________ have a negative charge and move in orbits of fixed size and energy
- 30. Experiments with ______ (Crookes) tubes(two words)
- 31. every radioactive element ______ in radioactivity over time
- 32. Bohr offered a place for many escaping ______ scientists to live and work after hitler took over germany.(religion)
- 35. Bohr's theory could explain why atoms emitted light in fixed __________.
- 37. JJ Thomson’s wife(two words)
- 38. J.J. Thomson was born(3 different sets of numbers;month,day,year)
- 42. J.J. Thomson discovered the ______ by experimenting with a Crookes, or cathode ray tube