Atomic Theory

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Across
  1. 4. A stable, positively charged elementary particle, found in atomic nuclei in numbers equal to the atomic number of the element
  2. 5. created atom with nucleus and electrons orbiting it
  3. 6. came up with idea that all matter contains atoms
  4. 7. famous for his discovery of the charge of the electron
  5. 8. A stable elementary particle present in all atoms, orbiting the nucleus in numbers equal to the atomic number of the element in the neutral atom
  6. 11. One of a class of substances that cannot be separated into simpler substances by chemical means
  7. 12. An elementary particle having no charge, mass slightly greater than that of a proton
Down
  1. 1. famed for his contributions to quantum mechanics
  2. 2. discovered the neutron
  3. 3. discovered that each element of an atom contained an original positive charge within their nucleus
  4. 9. discovered the electron
  5. 10. The smallest quantity of an element that can take part in a chemical reaction