Periodic Table

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

A chemist who developed the periodic table and organized elements by their properties while leaving empty spaces for more elements to be discovered

A pure substance that cannot be broken down.

A row going across on the Periodic Table

A column going up and down on the Periodic Table

The pattern of repeating properties down each group in the periodic table

A one or two letter symbol that represents that name of an element

number of protons in an element, atomic # is also equal to the number of electrons

The number of protons and neutrons in the nucleus (center) of an element

A material that allows things to flow

elements that are good conductors of heat and electric current

elements that are poor conductors of heat and electric current

elements with properties that fall between those of metals and nonmetals

Elements in group 18, stable and unreactive

A particle with a positive charge, same amount as atomic number, this particle identifies the element

A particle with a neutral charge, same amount as (atomic mass - atomic number)

A particle with a negative charge, same amount as atomic number

Electrons on the outermost shell

Outer boundary of an atom, mostly empty space, each shell starting from the first shell can hold: 1st shell - 2 electrons 2nd shell - 8 electrons 3rd shell - 18 electrons 4th shell - 32 electrons

the center of an atom that contains neutrons and protons and therefore most of the mass

a force of attraction between atoms to make them more stable

when atoms transfer electrons and become charged particles

the force of attraction that holds together positive and negative ions, a transfer of electrons

A force of attraction that holds together two atoms and shares electrons