electron structure

electron shell

a group of atomic orbitals with the same principle quantum number

subshell

a group of orbitals of the same type within a shell

orbital

a region within an atom that can hold up to two electrons with opposite spin

number of electrons in shell 1

up to 2

number of electrons in shell 2

up to 8

number of electrons in shell 3

up to 18

number of electrons in shell 4

up to 36

types of orbitals

s, p, d, f

shape of s orbitals

spherical shaped

shape of p orbitals

dumbell shaped

number of s orbitals per shell

1

number of p orbitals per shell

3

number of d orbitals per shell

5

number of f orbitals per shell

7

total number of protons and neutrons in a nucleus

mass number

number of protons/electrons

atomic number

what do orbitals show

the areas of greatest probability of finding an electron

why do electrons occupy orbitals on their own

to minimise repulsion and create more stability

electron configuration for argon

1s2 2s2 2p6 3s2 3p6

electron configuration for chromium

1s2 2s2 2p6 3s2 3p6 4s1 3d5

electron configuration for copper

1s2 2s2 2p6 3s2 3p6 4s1 3d10

which electrons are lost first during ion formation

highest energy electron

order of electron loss

4s electrons lost first, then 3d electrons because once 4s and 3d are filled, 4s moves above 3d in terms of energy

rule for first row transition metals

lose s electrons before d electrons

isoelectronic

the same electron configuration