Download Atoms - Science with Mrs. Schulte

Atomic
Structure
Notes
Matter
 Definition:
Anything that has mass and
takes up space
 The
“stuff” that makes up all substances
Elements
 The
purest forms of matter
 Cannot be broken down
 Elements bond together to form
molecules, which make up every
substance on Earth
 Most are found in nature, a few are
synthetic (man-made)
Atoms
 The
basic unit of an element
 Atoms of different elements are
different
Different size
 Different properties
 Different bonding

 All
atoms of a particular element are the
same
Atomic Size
So what do atoms look like?
(This should be review!)
Parts of an atom:
Draw this AND label in the box on your paper
Electron
Nucleus
Neutron
Proton
Electron
Cloud
Proton
 Positively
 Located
charged particle
in the nucleus
Neutron
 Neutrally
 Also
charged particle (NO charge)
located in the nucleus
Electron
 Negatively
 Located
charged particles
in the electron cloud
Nucleus
 The
center of an atom
 Includes
the protons and the neutrons
Now that we have reviewed
the structure of the
atom…let’s go back to the
periodic table
REMEMBER
Atoms are the basic units of elements
AND The Periodic Table is how we
organize all these elements!
Periodic
Table
Notes
What does
periodic
mean?
Happening
at regular intervals
Who created the
periodic table?
 Dmitri
Mendeleev
created the first
periodic table
 Published in 1869
 Russian chemist
How did he arrange it?
 Arranged
by increasing atomic #
 Also arranged in rows and columns,
where elements share properties with
the other elements in their groups
 Periods-
this is what we call ROWS on a
periodic table
 7 periods
 Groups-
this is what we call COLUMNS
on a periodic table
 18 groups
Reading Each Element
Draw this AND label in the box on your paper
1
Atomic #
Chemical
Symbol
1.008
Hydrogen
Atomic
Mass
Element
Chemical Symbol
Abbreviation
or short
representation of the
chemical name of an
element
Atomic number:
The number of
protons in an
atom
Atomic mass
The average mass of
all the isotopes
(different types) of
an element
Mass number
Total # of protons and
neutrons in an atom.
(Round the atomic
mass to get the mass
number)
Calculating Parts of the Atom
Protons
=Atomic
#
Neutrons
Mass number
(protons +neutrons)
Atomic number
(protons)
Electrons
= Atomic #
The number of electrons
in an atom is equal to
the number of protons.
(why?)
FYI: Isotope
 When
an element has the same # of
protons, but has a different # of
neutrons in the nucleus.
 This
can create two of the same
elements with different mass #’s, which
is the reason we have an atomic mass.