 
Allright.
Welcome back to another MCAT
Mnemonic Monday.
I'm Ken and I'm an MCAT expert
with MedSchoolCoach.
Today we have another general
chemistry mnemonic for you
and that mnemonic is for
periodic trends.
The periodic trends tell you
in which direction
of the periodic table do you
have increasing
values for different chemical
properties.
The mnemonic is bear: B
E A R.
And each letter stands for
different chemical properties.
B stands for basicity,
the ability of molecules to
accept protons.
As you can see, basicity
increases going
up and to the left of the
periodic table.
E stands for three things:
Electronegativity,
Electron affinity, and
ionization Energy.
All of these E's increase
going
up and to the right of the
periodic table.
Electronegativity is the
ability of an atom
to attract electrons to itself
at a covalent bond.
Electron affinity is the
energy associated
when you add an electron to an
atom.
Ionization energy is the
amount of energy
required to remove an electron
from an atom.
Next we have A, which stands
for Acidity.
This is the ability of a
molecule to donate protons and
solution.
Acidity increases going down
and to the right on the
periodic table.
And finally we have R which is
Radius.
Radius is the size of an
atom's electron cloud
and it increases going down
and to the left on the
periodic table.
So again the mnemonic is Bear:
B E A R.
