Across
- 6. Negatively charged subatomic particles that constantly move in the spacious regions surrounding the nucleus.
- 8. Energy Levels The specific, concentric zones or pathways surrounding the nucleus where electrons travel.
- 11. A horizontal row on the periodic table. The period number indicates how many total electron shells an atom uses to hold its electrons.
- 12. A one- or two-letter abbreviation used to represent a specific element (e.g., C for Carbon, Na for Sodium). The first letter is always capitalized, and the second letter is always lowercase.
- 14. Neutrally charged (no charge) subatomic particles located inside the nucleus alongside the protons.
Down
- 1. The absolute outermost electron shell of an atom that contains electrons.
- 2. An organized chart that lists all known chemical elements arranged systematically according to their atomic structures and repeating chemical properties.
- 3. The fixed number of protons found in the nucleus of an atom. This number uniquely identifies the element and dictates its position on the periodic table.
- 4. An atom that has a completely full outermost valence shell (containing either 2 electrons for the first shell, or 8 electrons for the outer shells), making it safe, secure, and highly unreactive.
- 5. The electron or electrons occupying the valence shell. These outer electrons are directly responsible for how an atom bonds and reacts chemically with other elements.
- 7. Positively charged subatomic particles located tightly inside the nucleus of an atom.
- 9. An atom that has an equal number of positive protons and negative electrons, resulting in a net electric charge of zero.
- 10. A vertical column on the periodic table. Elements in the same group share the same number of valence electrons and exhibit highly similar chemical behaviors.
- 13. A decimal number indicating the total average mass of an atom, calculated primarily by adding the number of protons and neutrons together inside the nucleus.