TRENDS
Trend in Atomic Radius
Atomic
Radius:
The size of
an atom is
determined
by the
boundaries
of the
valence e-.
The largest
atoms are
those found
in the lower-
left corner
since these
atoms have
the largest n
(most shells).
Trend in Ionization Energy
Ionization
energy:
The energy
required to
remove the
valence electron
from an atomic
species. The
ionization energy
is largest toward
the upper-right
corner of PT
since these atoms
hold on to their
valence e- the
tightest.
Trend in Electronegativity
Electronegativity:
Indicates the relative
ability of an atom to
attract electrons in a
chemical bond.
Arbitrary units
called Paulings (after
Linus Pauling) are
used to express
electronegativity.
Electronegativity
increases from left to
right across a period
and from top to
bottom down a http://www.webelements.com/webelements/properties/text/image-
group. intensity/electroneg-pauling.html
Summary of Trend
Periodic Table and Periodic Trends
Electron Configuration Ionization Energy: Largest toward UR of PT
Electronegativity: Largest toward UR of PT
Atomic Radius & Ionic Radius: Largest toward bottom-left corner of PT