Periodic Trends Terms

Group 2 elements: less reactive, more dense metals that form solutions in water that have a pH greater than 7.

• Transition metals
• Noble gases
• Alkaline earth metals
• Halogens

Group 18 elements: once known as "inert" these elements are considered stable because they have a full set of outer level electrons.

• Halogens

• Noble Gases

• Alkali Metals

• Carbon Family

Most of these elements are gases at room temperature, but some are solids which do not conduct electricity, and are considered to be dull in appearance.

• Nonmetals

• Metals

• Metalloids

A horizontal row in the periodic table.

• group
• period

A vertical column in the periodic table.

• Period

• Group

The Russian chemist credited with developing the first periodic table, with the elements in order of atomic mass.

• Dmitri Mendeleev
• Marie Curie
• Henry Moseley

Defined as one half the distance between two unbonded atoms.

• Atomic radius

• Electronegativity

• Ionization Energy

The energy needed to REMOVE an electron from a gaseous atom.

• Ionization energy
• Atomic radius
• Electronegativity

The ability of an atom to attract electrons, within a covalent bond, to itself.

• Atomic radius

• Ionization energy

• Electronegativity

The principle that states that the properties of the elements repeat themselves at regular intervals.

• random rule
• chaotic law
• sporadic principle
• periodic law