Transcript Periodic Trends

Periodic Trends
Definitions
& Trends
ELECTRONEGTIVITY
 Electronegativity
is the power of
an atom, when in a molecule, to
attract electrons to itself.
Electronegtivity Increase across --->
Decrease down
ATOMIC RADII
 1/2
the distance between the
nuclei two like atoms
Different Atomic Radii
Atomic Radii decrease across ------>
increase down
IONIC RADII
 The
radius of an atom after it has
gained or lost an electron and
becomes an ion
Ionic Radii Increase Across ---->
Increase Down
IONIZATION ENERGY
 energy
necessary to remove an
electron from the neutral atom.
Ionization Energy Increase Across ---->
Decrease down
ELECTRON AFFINITY

is a measure of the energy
change when an electron is
added to a neutral atom to form a
negative ion.
Electron Affinity Increase Across ---->
Decrease Down
Electron Shielding

The effects of the inner electron shell on
the outer most electrons
Increase Down
 Generally decreases across

Atomic Number & Mass
 Atomic
Number is the number of
protons in an element
 Atomic mass is the relative
average mass of an element
Atomic number & mass
Increases across --->
Increases down
Melting and Boiling Point

Generally increase across the chart until d
orbitals become half filled then Mp and
Bp decrease