Chapter 5 Vocabulary

one twelfth the mass of a carbon-12 atom

• atomic mass unit (amu)
• period
• group
• periodic law
• metals

elements with properties that fall between those of metals and nonmetals

• metalloids
• period
• group
• periodic law
• atomic mass unit (amu)

a column of elements in a periodic table

• group
• period
• periodic law
• atomic mass unit (amu)
• metals

a row in the periodic table of elements

• period
• group
• periodic law
• atomic mass unit (amu)
• metals

the elements in Group 8A of the periodic table

• Noble gases
• Periodic Table
• Valence electron
• Alkali metals
• Alkaline earth metals

the elements in Group 1A of the periodic table, not including hydrogen

• Alkali metals
• Periodic Table
• Valence electron
• Alkaline earth metals
• Halogens

an electron that is in the highest occupied energy level of an atom

• Valence electron
• Periodic Table
• Alkali metals
• Alkaline earth metals
• Halogens

an arrangement of elements in columns, based on a set of properties that repeat from row to row

• Periodic Table
• Valence electron
• Alkali metals
• Alkaline earth metals
• Halogens

the elements in Group 7A of the periodic table

• Halogens
• Periodic Table
• Valence electron
• Alkali metals
• Alkaline earth metals

elements that are poor conductors of heat and electric current

• nonmetals
• period
• group
• periodic law
• atomic mass unit (amu)