Unit 4 - Physcial Science
Across
- 3. Electron Levels/Orbits; Study of light
- 9. the mass of an atom expressed in atomic mass units
- 10. properties are between those of metals and non metals; semiconductors
- 14. a subatomic particle that has no charge and that is located in the nucleus of an atom
- 15. in chemistry, a horizontal row of elements in the periodic table; helps us determine the number of shells/ orbits
- 17. the number of protons in the nucleus of an atom; the atomic number is the same for all atoms of an element
- 18. Electron Clouds
- 21. Positive, Dense Nucleus; Gold Foil Experiment
- 22. an atom that has the same number of protons (or the same atomic number) as other atoms of the same element do but that has a different number of neutrons (and thus a different atomic mass)
- 23. metals Groups 3 - 12
Down
- 1. elements with 8 valence electrons
- 2. a vertical column of elements in the periodic table; elements in a group share chemical properties; helps us determine the number of valence (outer) electrons; generally help define properties of elements
- 4. Elements with 2 valence electrons
- 5. one of the elements of Group 17 of the periodic table (fluorine, chlorine, bromine, iodine, and astatine); halogens combine with most metals to form salts.
- 6. the sum of the numbers of protons and neutrons in the nucleus of an atom
- 7. one of the elements of Group 1 of the periodic table (lithium, sodium, potassium, rubidium, cesium, and francium)
- 8. mostly solids; shiny; good thermal conductors; good electrical conductors; malleable
- 11. Cathode Ray; Discovery of Electrons; Plum Pudding model
- 12. Brittle, Poor conductors, insulators; many are gases at room temperature
- 13. a unit of mass that describes the mass of an atom or molecule
- 16. Everything is made up of atoms; Each element's atoms were identical to each other; Each element's atoms differ from other element's atoms; Compounds were always the same types of atoms combining
- 19. Law the law that states that the repeating chemical and physical properties of elements change periodically with the atomic numbers of the elements
- 20. a subatomic particle that has a positive charge and that is located in the nucleus of an atom; the number of protons in the nucleus is the atomic number, which determines the identity of an element