Across
- 1. Formed when an atom loses one or more electrons
- 4. Elements in a row on the periodic table with one proton variation
- 6. Elements that almost never react with other elements
- 7. The rare earth elements with atomic numbers 58-71
- 8. A space in which electrons move around the nucleus
- 9. Positively charged particles
- 12. Formed when an atom gains one or more electrons
- 14. The measurement used for protons and neutrons (mass)
- 15. The most reactive elements on the periodic table
- 21. Very reactive metals that play a part in day to day human life
- 23. An element with properties opposite to those of a metal
- 24. Elements that are less reactive, and are some of the earliest known to man
- 25. An element with properties of metals and nonmetals
Down
- 2. An atom of the same element with a different number of neutrons
- 3. An element that conducts electricity/heat well, and has a shiny appearance
- 5. Uncharged/neutral particles
- 10. The process in which atoms produce energy and particles
- 11. Formed when an atom loses or gains one or more electrons
- 13. Found in the center of the atom, contains protons and neutrons
- 16. Negatively charged particles
- 17. The process of a radioactive atom changing its identity
- 18. Elements in a column on the periodic table with similar properties
- 19. Very reactive nonmetals that easily form compounds called salts with many metals
- 20. Elements on the periodic table that are metallic and radioactive, with the atomic numbers 90-103
- 22. Number of protons in the nucleus of an element