science

Atom

Smallest partial of an element

Protein

Subatomic particle located in the nucleus has a positive charge

Neutron

Subatomic particle located in the nucleus has a neutral charge

Electron

Subatomic particle located in the electron cloud has a negative charge

Quarks

Particles that make up protrons and neutrons

Valence electrons

e- in the outermost energy level of the electron cloud

Atomic number

Number of protrons in an atom periodic table is arranged by this number

Mass number

Number of protrons and neutrons in an atom

Isotope

Atoms of the same element with different numbers of neutrons

Average atomic mass

Weighted average of all the isotopes of a particular element

Groups

Vertical columns

Periods

Horizontal rows

Metals

Found on left side of table, mostly solids, shiny with metallic luster good conductors high melting points

Nonmetals

Upper right side of table anc be solids liquids and gases dull in appearance brittle as solids lower melting point

Metalloids

Found along the stair step line all are solids at room temp can have a metallic shine or luster brittle intermediate melting point