Periodic crosswords

4. Electron: Electrons in the outermost energy level of an atom; these are responsible for bonding and chemical reactions.
5. The principle that the chemical and physical properties of elements repeat in a predictable way when elements are arranged by increasing atomic number.
6. Gases: Chemically inert/unreactive gases in Group 18 with full valence shells.
7. Metals: Elements in groups 3 through 12, often forming colored compounds.
8. Earth Metals: Group 2 elements, which are reactive but less so than alkali metals.
10. Elements along the "staircase" line with properties intermediate between metals and nonmetals.
14. Elements that are generally gases or brittle, dull solids, and poor conductors of heat and electricity.
16. Energy: The amount of energy required to remove an electron from a gaseous atom.
18. The ease or speed with which an element combines or reacts with other elements or compounds.
19. & Actinides: The two rows usually separated at the bottom of the table, often called inner transition metals.
20. A one-, two-, or three-letter abbreviation used to represent an element.

1. A measure of an atom's ability to attract shared electrons in a chemical bond.
2. horizontal row on the periodic table; elements in the same period have the same number of electron energy
3. vertical column on the periodic table; elements in the same group often have similar chemical properties and the same number of valence electrons.
9. Radius: A measure of the size of an atom, usually the distance from the center of the nucleus to the boundary of the electron cloud.
11. Mass: The weighted average mass of all naturally occurring isotopes of an element, typically found below the element symbol.
12. Number: The number of protons in the nucleus of an atom, which determines the element's position on the table.Atomic
13. Metals: Group 1 elements, excluding hydrogen, which are extremely reactive soft metals.
15. Highly reactive nonmetals in Group 17.
17. Elements that are typically shiny, solid at room temperature, conductive, malleable, and ductile.