The second part of Molly Devine’s Awesome project.
Atomic Radius
Hi! I am Jamal the
Chemistry Elephant.
I will help you on
your journey to the
Taj Mahala of
Geniuses!
Atomic Radius
 The Atomic Radius is defined as half of the distance
between the nuclei of two adjacent atoms of the same
element.
So, it’s the
diameter
of the
atom

The Atomic Radius
Trends in Atomic Radius
 Elements with larger atomic charge have a smaller
radius because the attraction between the protons and
electrons is stronger. The elements with the smaller
atomic charge have a larger radius because the
attraction is not as strong.
 Therefore, the Atomic Radius increases as the group
on the table goes down and the period increases from
left to right.
The elements on
the bottom left
hand side of the
table have the
greatest atomic
radius!
The Atomic Radius
Trend
The Trend in atomic
Radius is shown by
the red arrow on the
table.
IONS!!!!
 Another trend that takes place on the periodic table is
the Ionization Energy trend.
 Ions are atoms or groups of atoms with positive or
negative charges.
 The ion can be a cation(positive ion). Cations are
usually formed by metals because they normally give
up their electron when they bond.
 Or they can be Anions(negative ions). These are
usually formed by non-metals because they gain
electrons when they bond.
Ionization Energy
 Ionization Energy is defined as the energy required to




REMOVE an electron from an atom.
There are 3 Ionization Energy Levels:
The first ionization energy is the energy required to
remove the first electron .
As we go to the 2nd and 3rd ionization energy levels, the
energy required to remove the electron increases.
The trend for this is explained in the chart on the next
slide.
Ionization Energy
Trend
The energy will
increase as one
moves to the left to
right through a
period and as ones
moves from bottom
to top. This trend is
shown by the red
arrow.
Trends in Ionization Energy
 The explanation for this trend is that ionization energy
in a periodic group depends on how far away an atom’s
electrons are to its nucleus. If they are closer to the
nucleus, the element will “hold on” to them, while
those that are located further away from the nucleus
are easily taken by other elements.
 In a period, ionization energy depends on the atom’s
tendency to achieve Noble Gas configuration.
Ion Size
 Even ions have a pattern in their size.
 Ionic size follows the same pattern as atomic size.
 The reasons for this are:

Anions gain electrons and therefore become larger.
 Cations loose electrons. Ergo they are smaller.
Hey, that
sounds
just like
atomic
radius!
Ion Size
Ionic size is indicated by
the red arrow to the
right.
Electronegitivity
 The last Periodic Trend is Electronegetivy.
 Electronegitivity is the ability of an atom to attract
electrons to when in a compound.
 The Trend in Electronegitivity increase from left to
right and also increases from top to bottom.
Elements in Group 7
attract electrons
more easily because
they only need so
few.
Electronegitivity Trend
 The reason for this trend
is elements in the groups
to the right can easily
attract electrons because
they only need a few.
 Elements on the bottom
of the table are less likely
to form compounds.
Now that you have
learned the
Periodic Trends…..
You have
entered
the Taj
Malahal of
geniuses!!!
Good job! Isn’t
great to be in
the Taj Mahala
of Geniuses?