ELECTRON ARRANGEMENT

3. How readily a substance undergoes a chemical reaction. For metals, reactivity often involves losing electrons to form positive ions.
5. An element that is generally not shiny, a poor conductor of heat and electricity, and often brittle in solid form (e.g., sulfur, oxygen).
7. An element that is typically shiny, a good conductor of heat and electricity, malleable, and ductile (e.g., iron, copper).
9. Likely to break or shatter easily when struck, rather than bend. This is a typical property of many solid nonmetals.
10. A material that allows heat or electricity to flow through it easily. Most metals are good conductors.
13. Refers to the outermost shell of an atom. The electrons in this shell (valence electrons) are involved in chemical bonding.
14. Also called an energy level; the region around an atomic nucleus where electrons are arranged. Shells are filled from the innermost outward.
15. A vertical column on the Periodic Table. Elements in the same group have similar chemical properties and the same number of valence electrons.

1. A visual representation, such as a dot-cross diagram, which uses dots and crosses to show the arrangement of outer shell (valence) electrons.
2. A characteristic used to describe and identify a substance. Here, it refers to physical and chemical properties used to classify metals and nonmetals.
4. An atom or molecule that has gained or lost one or more electrons, giving it a positive or negative electrical charge.
6. The property of having a shiny, reflective surface. This is a characteristic metallic property.
8. A negatively charged subatomic particle that orbits the nucleus of an atom. Its arrangement determines chemical properties.
11. Able to be hammered or rolled into thin sheets without breaking. This is a key property of most metals.
12. Referring to the Periodic Table, the chart where all known elements are organized based on their atomic number and properties.