Chem Lecture: Multi Electron Atoms

Front 1

Nuclear Charge

Back 1

Negatively charged electrons experience an attraction to the positively charged nucleus

Front 2

Shielding

Back 2

When two or more electrons are present, both electrons experience a decreased amountof nuclear charge. Electrons in a higher principle shell (n), or outer electrons, experience a greater amount ofshielding from inner electrons

Front 3

Penetration

Back 3

The closer the smaller maxima lies to the nucleus, the greater the attractive force. Electrons in different subshells will penetrate the inner shell differently

Front 4

Pauli Exclusion Principle

Back 4

No two electrons can have the same four quantum numbers

Front 5

Aufbau Principle

Back 5

Electrons generally will occupy the most stable atomic orbitals (lowest energy, see the electron configuration diagram from multi-electron atoms) bottoms up

Front 6

Ground state electron configuration

Back 6

When all electrons occupy the lowest energy atomic orbitals

Front 7

Hunds Rule

Back 7

In the case of degenerate orbitals, electrons will prefer to occupy differentdegenerate atomic orbitals rather than be paired up in the same atomic orbital

Front 8

Notable Exceptions in Electron Configurations

Back 8

In the electron configuration of Copper the d subshell will be filled at the expense ofunpairing the electrons in the s subshell. In the electron configuration of Chromium the d subshell will be half-filled at theexpense of unpairing the electrons in the s subshell- Remember that the 4s and 3d orbitals are close in energy so transferring an electronfrom one subshell to another does not cost much energy

Front 9

s block

Back 9

Groups 1 and 2

Front 10

d block

Back 10

groups 3 - 12

Front 11

P block

Back 11

groups 13-18

Front 12

Non bonding atomic radius

Back 12

describes ½ the distance between two atoms in a solid state lattice

Front 13

Bonding atomic radius

Back 13

describes ½ the distance between two atoms that are connected through a chemical bond

Front 14

Ionization Energy

Back 14

The energy required to remove an electron from an atom in the gaseous state. It always refers to the highest energy (most easily removed) electron present.

Front 15

Electron affinity

Back 15

Defined as the energy that is released when a gaseous atom gains an electron.

Front 16

Electronegativity

Back 16

Defined as the capability of an atom to attract electrons in a covalent bond towards itself.

Front 17

degenerate

Back 17

When there is only one electron a