periodic trends

Dmitri Mendeleev

Organized the periodic tables by atomic mass and predicted missing elements

henry Moseley

arranged the elements by atomic numbers

Cation

Positive ion lose electron

Anion

negative ion gain electron

isoelectric

same number of electrons during ionization

How does radius effect atoms

bottom-top: energy levels=bigger atom

Right-left: less protons= less zeff on electrons= larger radius

How does ionization effect atom

bottom-top: less energy levels=harder to remove electrons=more ionization energy required

left-right: More protons= more Zeff= stronger pull on the energy levels= more ionization required to remove electrons

How does electronegativity effect atom

Bottom-top: less energy levels=more zeff=strong electronegativity on electrons

Left-right: more protons= strong Zeff on electrons=strong electronegativity

HALOGENS cant attracy anymore electrons because already has octet

Octect rule

When ionization, all atoms will end with octect

Smallest atoms and largest

Francium large

helium small

Alkali Metals

group 1

reactive

low density

silver and shiny

Alkali Earth Metals

group 2

less reactive than normal alkali

More dense than alkali

Silvery

Halogens

are diatomic

very reactive

poor conductors

all non metals

noble gasses

not reactive

non metals

colorless gases

how to remember diatomic atoms

start at 7 and stop at element I

shielding effect on atom

Blockage of Zeff from inner electrons, so Zeff decreases while ionization increases

First exception to ionization energy

between group 2 and 3

Easy to remove an electron from group 3 bc p energy level does not hold electrons tightly together and penatrate a large nuclear charge

Second ionization energy exception

Between group 5 and 6

easy to remove an electron from group 6 because of the added repulsion from the paired electrons in p orbital, compared to 5 where p orbitals are all unpaired

Electronegativity exception

noble gases

metals related to ionization is-

metals- lose electrons to form cations

Non metals- Gain electrons to form anion