Periodic Table Trends

element

A pure substance made of only one kind of atom

atom

the basic unit of a chemical element.

protons

Positively charged particles

neutrons

the particles of the nucleus that have no charge

electrons

Negatively charged particles

period

A horizontal row of elements in the periodic table

group

Vertical column in the periodic table

valence

Electrons on the outermost energy level of an atom

electronegativity

the ability of an atom in a chemical compound to attract electrons

ionization energy

The amount of energy required to remove an electron from an atom

atomic radius

size of an atom

metals

Elements that are good conductors of electric current and heat - located on left side of stair step line

non-metals

elements that are poor conductors of heat and electricity, found on right side of stair step line

metalloids

Elements that have properties of both metals and nonmetals.

stair step line

This is the boundary between the metals and non-metals on the periodic table