Using the Quantum Model
Periodic Table
Periodic Trends
• Atomic Radius: Increases down a group and
decreases across a period
• Ionization Energy (energy required to remove
an electron from the atom): Decreases down a
group and increases across a period
Ions
• Cations: lose electrons, electron configuration of
the cation is the noble gas core
General group 1: [NG]ns1  [NG]+ +1e• Anions: gain electrons, electron configuration of
anion is the following noble gas on the periodic
table
General group 17: [NG] ns2np5 +1e- 
[NG] ns2np6
Become isoelectric to the noble gas (same number
of electrons)
Magnetism: classified by strongest
magnetic property
• Diamagnetic: weak interaction with a magnetic
field, material is slightly repelled by magnetic
field
– All material has diamagnetic properties
• Paramagnetic: material is attracted into the
magnetic field, single electron in an orbital
(unpaired electron)
• Ferromagnetic: material is attracted to a magnet
or form magnetic material. Higher number of
unpaired electrons.
Anomelies
• Pairing raises the energy slightly, a half filled subshell
and a full filled subshell lower the energy (gaining
some stability)
Possibilities:
• Will half fill both s and d orbitals (Cr, Mo, W)
• Will half fill s orbital and fill d orbital (Cu, Ag, Au)
• Will fill d orbital and have empty s orbital (Pd)
Applications of Quantum
Mechanics
Lasers
• Uses Planks theory: excite electrons and when
they relax back to ground state the photon
released produces light
MRI’s
• Magnetic resonance imaging: uses nuclear
magnetic resonance principles
• Aligns the spins to one direction in the body
using a large magnet, followed by a pulse to
alter the alignment
• Nuclei produce a magnetic field which is
detected to create an image when they relax