Periodic Table of Elements History

empedocles (450BCE)

greek, love & strife

aristotle (384 BCE)

four elements- fire, air, water, earth

alchemist (medieval)

classified elements, grouped the elements

antoine lavoisier (1789)

father of chemistry

johann wolfgang dobereiner

law of triads

john newland (1864)

law of octaves

lothar meyer (1864)

arranged elements by atomic weight

dimitri ivanovich mendeleev

father of periodic table

electronegativity

atom’s ability to  attract and bind with electrons

ionization energy

energy required to remove an electron in its gaseous phase

atomic radius

distance from the nucleus to the outermost electron of an atom

periodic table has __ groups

18

periodic table has __ periods

7

sublevels

subdivision of energy level, describes the shape of the region where electrons are most likely to be found

orbitals

specific space within a sublevel (max of 2)

most complex of all

sublevel f

Sublevel S

spherical #1

Sublevel P

dumbbell #3

Sublevel D

cloverleaf #5

Sublevel F

Complex #7

electron configuration

describes how electrons are arranged within an atom or molecule

Aubau’s Principle

1s 2s…

Pauli’s Principle

mass number

total # of proton & neutron

atomic number

#of protons

neutron

mass number - proton

isotopes

stable % radioactive; atoms of the same element that have the same number of protons but different numbers of neutrons

empirical formula

simplified