Transcript 19.1 Notes - Trimble County Schools

Chapter 19 –
Properties of Atoms
and the Periodic table
19.1 – Structure of the Atom
Guided Notes Page
Objectives - 1-4
 Identify the names and symbols of
common elements.
 Describe characteristics and location of
atomic particles. (Composition and charge)
 Describe the electron cloud model of the
atom.
 Explain how electrons are arranged in an
atom.
Scientific Shorthand
 Chemical symbols
= used to
abbreviate the
name of an element
 Accepted and used
worldwide
http://www.ptable.com/
 One capital letter or one capital letter and
1-2 lowercase letters
 Some are simply the 1st (or 1st and
another letter) of the element’s name
 H = Hydrogen
Ca = Calcium
 Others are derived from the Latin name
of the element
 Ag = Silver
Fe = Iron
Latin names









Cu – Cuprum (Copper)
Au – Aurum (Gold)
Fe – Ferrum (Iron)
Pb – Plumbum (Lead)
Hg – Hydrargyum (Mercury)
K – Kalium (Potassium)
Ag – Argentum (Silver)
Na – Nathum (Sodium)
W – Wolfram (Tungsten)
Atomic Components
 Atom = smallest piece of matter that
retains properties of the element
 Atomic Particles
 Protons (p+) = positive charged particles
 Neutrons (no) = uncharged particles
 Electrons (e-)= negative charged particles
 Protons and Neutrons are found in the
nucleus of an atom
Quarks
 Scientists confirm that p+ & no are made
of smaller particles called Quarks
 6 uniquely different quarks
 Arrangement of 3 = proton
 Different arrangement of 3 = neutron
http://faculty.washington.edu/smcohen/320/Democritus.jpg
Atomic Model
 400 B.C. – Democritus
proposed the idea that atoms
make up all substances
 Aristotle disputed Democritus'
theory and said matter was
uniform throughout and not
composed of smaller particles
 Aristotle had more clout and his
theory held for more than 2000
years
http://academic.shu.edu/honors/aristotle.jpg
Atomic Model
 1800s – John Dalton
was able to prove
atoms exist
 Solid sphere = atom
 Provided physical
explanation for chemical
reactions
http://wind.cc.whecn.edu/~mechalke/chapter5/Thomson.gif
Atomic Model
 1904 – J.J. Thomson said
electrons were found
throughout positive sphere
 1911 – Ernest Rutherford
said atoms was not a
sphere but rather a central
mass (nucleus)
surrounded by electrons
http://www.cfo.doe.gov/me70/manhattan/images/AtomLabeled.gif
Atomic Model
 1913 – Niels Bohr said electrons move in
fixed orbits
http://www.green-planet-solar-energy.com/images/bohr_atom.gif
Atomic Model - current
 Electron Cloud Model
= area around nucleus
where electron likely to
be found
 Electrons move so
quickly it is difficult to
pinpoint exact location
 Electrons do not follow a
rigid pattern of
movement
In-Class
Assignment/Homework
 19.1 Reinforcement WKT
Modeling an Aluminum Atom
 Gather 13 blue dots, 13 green dots and 14 red
dots
 Arrange all blue dots and all red dots on a flat
surface to represent the nucleus of an atom
 Each blue dot = proton
 Each red dot = neutron
 Position 2 green dots 2 cm from the nucleus
 Position 8 green dots 5 cm from the nucleus
 Position 3 green dots 8 cm from the nucleus
 Answer questions from pg. 581 on
back of paper