Transcript CHE 106 Chapter 2x

CHE 106
Chapter Two
ATOMS, MOLECULES AND IONS.
How has the atomic theory evolved?
How has the atomic theory evolved?
How has the atomic theory evolved?
Dalton’s Atomic Theory:
1.
2.
3.
4.
How has the atomic theory evolved?
The Law of Constant Composition and Law of
Conservation of Mass lead to the:
Law of Multiple Proportions:
How has the atomic theory evolved?
How has the atomic theory evolved?
Landmark experiments led to the discover of the
electron, mass of the electron and charge on the
electron.
J.J. Thomson: Cathode Ray Tube Experiments
Robert Millikan: Oil Drop Experiment
How has the atomic theory evolved?
http://www.pixton.com/comic/r17ynu2t
How has the atomic theory evolved?
 Robert Millikan Oil Drop Experiment
Cathode Ray Animations
http://www.youtube.com/watch?v=GzMh4q-2HjM
http://www.hscphysics.edu.au/resource/template.swf
How has the atomic theory evolved?
After J.J. Thomson and Millikan’s experiments,
scientists had sufficient evidence to suggest that atoms
were made of much smaller particles. No longer
believed that the were solid and indivisible.
Their work led to the discovery of the negative
particles, other scientists’ work led to the discovery of
the positive counterpart to the electron: the proton.
How has the atomic theory evolved?
Radioactivity: Wilhelm Roetgen and Henri Becquerel
CRT
metal
target
e beam
X-rays
invisible
radiation
(X-rays)
- not affected by magnetic fields
- passed thru many materials
-produced images on film
(ionized Ag emulsions)
How has the atomic theory evolved?
Henri Bequerel – credited with
discovering radioactivity.
Uranium and Radioactivity:
Curie’s Contribution:
How has the atomic theory evolved?
How has the atomic theory evolved?
Ernest Rutherford: further studied the radioactivity
and was able to come up with determine the relative
charge and speed of the three types of radioactive
particles.
Alpha:
Beta:
Gamma:
How has the atomic theory evolved?
Gold Foil Experiment
Conclusions
1.
2.
What is the internal makeup of a modern atom?
The charge and size of an atom are two measurements
that have been quantified and then simplified for ease
of use.
Electronic Charge:
What is the internal makeup of a modern atom?
The size and mass of the atom has been determined
experimentally, and units have been assigned to these
measurements.
Atomic Mass Unit (amu)
Angstroms
What is the internal makeup of a modern atom?
Example: How many gold atoms are there in the post of a
gold earring that measures 5.6mm long. A gold atom has a
diameter of 1.35 Angstroms.
http://www.onemorelevel.com/game/scale_of_the_unive
rse_2012
What is the internal makeup of a modern atom?
Composition of the atom and other related terms:
Atomic Number (Z) :
Mass Number(A):
Isotopic Notation:
Atomic Weight:
What is the internal makeup of a modern atom?
 Example 1: Verify that the atomic mass of magnesium is
24.31, given the following:

24Mg=
23.985042amu, 78.99%

25Mg=
24.985837 amu, 10.00%

26Mg=
25.982593, 11.01%
What is the internal makeup of a modern atom?
Example 2: The atomic mass of lithium is 6.94, the
naturally occurring isotopes are 6Li = 6.015121
amu, and 7Li = 7.016003 amu. Determine the
percent abundance of each isotope
How are the elements arranged on the PT
Groups:
Periods:
Naming Schemes:
How are the elements arranged on the PT
 Properties of Metals:
 Properties of Non-Metals
 Metalloids:
Chemical Nomenclature
Types of Formulas:
Molecular Formulas:
Empirical Formulas:
Structural Formulas:
Chemical Nomenclature
A compound has an molecular formula of
C36H36N24O12. What is the empirical formula?
Chemical Nomenclature
Chemical Nomenclature
Cations:
Anions:
Polyatomic Ions:
Chemical Nomenclature
Chemical Nomenclature
Chemical Nomenclature
Empirical Formula Practice:
Sodium and Phosphate:
Magnesium and Sulfate
Iron (III) and Carbonate
Chemical Nomenclature
Inorganic (Ionic) Nomenclature Guidelines
Cation:
*Positive polyatomic ions*
Roman Numeral vs. “Common” Names: “ic” vs. “ous”
Chemical Nomenclature
Guidelines continued…
Anions:
Negative polyatomic ions / oxyanions:
Chlorate
Chlorite
Hypochlorite
Perchlorate
Sulfate vs. Hydrogen Sulfate
Chemical Nomenclature
Ionic Nomenclature Practice
FeO
NaCl
Fe2O3
NaClO3
(NH4)2SO4
NaClO4
(NH4)2SO3
Na2O2
Chemical Nomenclature
Acid Nomenclature:
Cation:
Anion: 2 options:
For acids where H+ and Single Element:
Chemical Nomenclature
For acids with H+ and P.A.I
“ate”
“ic”
H2SO4
H2S
H2SO3
HCl
Chemical Nomenclature
Inorganic Naming and Writing Practice:
1.
2.
3.
4.
5.
6.
7.
Nitrous Acid
Hydroiodic Acid
H2CO3
KMnO4
CoS
Iron (III) carbonate
Sodium Hypobromite
Chemical Nomenclature
Molecular Nomenclature Guidelines
1.
2.
3.
4.
Chemical Nomenclature
 N2O5
 Iodine Heptafluoride
 Dihydrogen selenide
 Tetraphosphorous hexoxide
 Organic Nomenclature
 Alkanes
 Substituted Alkanes: Alcohols
 Isomers:
Draw, name and give the formula for the 3 isomers of
pentane.
What is the alcohol derived from butane? Write the
formula, draw the molecule and name.