150 likes | 271 Views
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)
E N D
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
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
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://faculty.washington.edu/smcohen/320/Democritus.jpg Atomic Model 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