A Review of Early Atomic Models,
Periodic Table Development, and
Nomenclature

Democritus (Greek)
 world is made up of::
 empty space
 tiny particles (atomos)

Aristotle (Greek)
 world is composed of continuous matter (hyle)
 accepted until 17th Century

agreed with Newton and
Boyle
 atoms were the basis (no
proof)


English
studied Lavoisier and
Proust (both were
French)

Chemical change in a
closed system has equal
mass before and after the
change, matter is neither
created nor destroyed
 Law of Conservation of Mass

Law of Definite Proportions
 Specific substances always contain elements in
the same ratio by mass
 example: H2O has a ratio of 1:8 (H:O)

Law of Multiple Proportions
 certain elements can combine to form two or more
different chemical compounds

Hydrogen and Oxygen can to form water (1:8)
and peroxide (1:16)



All matter is composed of extremely small
particles called atoms.
Atoms of a given element are identical in size,
mass, and other properties; atoms of different
elements differ in size, mass, and other
properties. (*)
Atoms cannot be subdivided, created, or
destroyed. (*)


Atoms of different elements can combine in
simple, whole-number ratios to form chemical
compounds.
In chemical reactions, atoms are combined,
separated, or rearranged.

These tennets are no longer true today!
 #2 because of isotopes
 #3 because of subatomic particles
~1832: FARADAY:
PROPOSED EXISTANCE OF ELECTRON
PROPOSED ELECTRICITY WAS CARRIED
BY CHARGED ATOMS ----IONS
~1879: CROOKES: INVENTED GAS DISCHARGE TUBE (CRT)
RAY FROM - “POLE” (CATHODE)
TO + “POLE (ANODE)
1895: ROENTGEN: CRT HIT TARGET, GET LOWER ENERGY
EMISSIONS ---- X-RAYS
1896: BEQUEREL: DISCOVERED RADIOACTIVITY!
1897: JJ THOMSON USED CRT AND EXPLORED NATURE
OF THESE “RAYS”

J. J. Thomson (Eng)
 cathode ray tube
experiment proved
that the atom is
divisible
 cathode (negative
electrode)
 anode (positive
electrode)
ZnS
-
+
+
NO CHARGE ON PLATES
1. RAY DEFLECTED BY ELECTRIC & MAGNETIC FIELD
NOT LIGHT; THEREFORE, PARTICLES
2. DEFLECTION TOWARD POSITIVE PLATE
PARTICLES NEGATIVELY CHARGED
3. LARGE DEFLECTION
DETERMINED CHARGE/MASS (q/m) RATIO
q/m < 1/1000 THE MASS OF HYDROGEN ATOM!!!!
THOMSON:
“FOUND” FARADAY’S ELECTRON
DETERMINED THE ATOM WAS NOT THE
SMALLEST PARTICLE
1909: MILLIKEN DETERMINED THE EXACT CHARGE
AND MASS OF THIS ELECTRON
ALL DATA INTEGRAL VALUES OF SAME NUMBER
q = -1.6 x 10-19 C
m = 9.1 x 10-31 kg
ABOUT 1/1800th OF THE HYDROGEN ATOM
1.60219 x 10-19 C
TODAY:
9.10940 x 10-31 kg
+
+
+

Robert Millikan (USA)
 Oil Drop Experiment
 first to measure the
mass of an electron
 9.109 x 10-28g
 first to measure the
charge of an
electron
 (-1)

What is a nucleon?
 A nucleon is a particle that is found within the nucleus
of an atom.

What are the major nucleons?
 Proton and the Neutron

Gold Foil Experiment
 hit a thin piece of gold foil
with a beam of alpha
radiation (positively
charged)
 some of the beam
went through
uninerrupted
 some of the beam was
deflected to the side
or totally reflected
1911 -- RUTHERFORD’S “GOLD FOIL” EXPERIMENT
ZnS COATED
STREAM
1. MOST PASS THRU UNDEFLECTED
SCREEN
OF a (ALPHA)
MOST OF ATOM VOLUME IS
PARTICLES
EMPTY SPACE
2. SOME POSITIVE a PARTICLES
DEFLECTED SLIGHTLY
GOLD
FOIL
NEAR COLLISIONS WITH MASSIVE,
POSITIVELY CHARGED PARTICLE
3. 1 OF 20000 DEFLECT ACUTELY
CROSS SECTION OF MASSIVE, POSITIVELY CHARGED
PARTICLE IS 1/20000th THAT OF ATOM
RUTHERFORD FOUND THE NUCLEUS!!!

Since the positively charged radiation was
repelled in certain areas, there was evidence
for a positive entity inside of the foil
 Proton


This led to the idea of a central core that is
very dense (nucleus)
Since some of the radiation passes through
unharmed the foil must not be totally positive
ATOM MUST BE A VERY DENSE, POSTIVELY CHARGED
NULCLEUS SURROUNDED BY VERY LIGHT, NEGATIVELY
CHARGED ELECTRONS
QUANDRY:
HEAVY PROTON (+ CHARGE) IN NUCLEUS
LIGHT ELECTRONS ON OUTSIDE
COMBINED, ACCOUNT FOR ~ 1/2 THE ATOMIC MASS
AND THE ATOM IS NEUTRAL!
1932: CHADWICK ISOLATED THE NEUTRON
IN NUCLEUS
O CHARGE
MASS ~ SAME AS PROTON

If the nucleus is the home
of the majority of the
mass, and the atom is
electrically neutral there
must be a neutral particle
with a mass: neutron

Proton
 +1 Charge
 Mass:1.673 x 10-24g
 number of protons
must equal the number
of electrons for the
atom to be neutral
 p+

Neutron
 No charge
 Mass:1.675 x 10-24g
 no
 nuclear force
holds the
particles
together in the
nucleus

Isotopes are atoms of the same element that
have different masses (different numbers of
neutrons).

Atomic Number
Z
 number of protons

Mass Number
A
 number of protons plus
the number of
neutrons

Using the periodic table
locate the symbol for the
element that you are
looking for. Inside the
element’s square will be
the numbers.
X
 Copper
 Oxygen
 Silver
Name of Isotope
Protium
Deuterium
Tritium
Atomic #
1
1
1
Mass #
1
2
3
o
n
0
1
2




Z = protons therefore protons = 29
Protons = Electrons therefore electrons = 29
A - Z = neutrons so 65 - 29 = 36, there are 36
neutrons
Now try Oxygen and Calcium:

Ions have charge due to an imbalance in
the number of protons and electrons.
Atoms can either gain or lose electrons.
If they gain electrons the ion is negative
(anion), where is they lose electrons the
charge is positive (cation).

O 2-

Ca 2+


Purpose: to determine
the average atomic mass
of a new element called
Beanium
Beanium has 3 isotopes:
black, black-eyed pea,
and speckled bean.



If you are given a sample of Beanium, what do
you need to know in order to calculate the
average atomic mass.
REMEMBER, that means the average mass of all
three isotopes!
Number of each type, mass of each type, and
then total to get the average mass per atom
(bean)
Type of
Isotope
Mass of
Isotope
(g)
Number
of
Isotope
Average
Mass of
Isotope
% of
Each
Present
Black
Blackeyed pea
Speckled
Total
100



A gaseous sample is introduced into the
spectrometer and then it is bombarded by a
stream of high-energy electrons.
Collisions between the electrons and the sample
produce cations (usually 1+)
The positive beam passes through magnetic
poles and bends, the more massive the sample
the less the bend of the ray
A full diagram of a mass spectrometer
Valence e- Oxidation #
Column #
Family Name
1
Alkali Metals
1
1+
2
2
2+
3
Alkaline Earth
Metals
Boron Family
3
3+/5-
4
Carbon Family
4
4+/4-
5
Nitrogen Family
5
3-
6
Chalcogens
6
2-
7
Halogens
7
1-
8
Noble Gases
8
0



Loose electrons (oxidation) to form ions that are
positively charged (cations)
Good conductors (allow energy to flow through
them) of heat and electricity
Have 3 or less valence electrons



Gain electrons (reduction) in order to form
negatively charged ions (anions)
Good insulators (don’t allow heat or electricity to
flow through them)
4 or more valence electrons



Found on the periodic table along the “staircase”
Have properties of both metals and non-metals
depending upon the particular situation
Also called the semi-metals


An assembly of two or more atoms tightly bound
together
Represented by a chemical formula (written as a
collection of element symbols and subscripts to
indicate the # of each element)


Some elements exist in nature as pairs of atoms:
diatomic “H and the 7”
NOF
 Br
 Cl
 I


Simplest, true formula of a compound
C2H8 can be simplified to CH4

The TRUE formula for the ratio of elements in a
compound
HELLO……MY NAME IS
51
MONOATOMIC CATIONS
ELEMENT + ION OR ELEMENT(VALENCE) + ION
Na1+SODIUM SODIUM ION
Al3+
ALUMINUM ION
Ca2+
CALCIUM ION
Fe2+
IRON (II) ION
Fe3+
IRON (III) ION
Li1+
LITHIUM ION
WHAT IS?
Be2+
Co3+
BERYLLIUM ION
COBALT(III) ION
Mn5+
MANGANESE(V) ION
52
MONOATOMIC ANIONS
ELEMENT ROOT + -IDE + ION
OO2-
OXYGEN
I
IODINE
I1-
OX IDE
ION
IODIDE ION
WHAT IS?
S2-
SULFIDE ION
Br1-
N3-
NITRIDE ION
Se2BROMIDE ION
SELENIDE ION
53

Higher Oxidation States for Transition metals is
indicated by the –ic suffix to the Latin stem
 Fe3+ is Iron (III) or ferric

Lower oxidation States for Transition metals is
indicated by the –ous suffix to the Latin stem
 Fe2+ is Iron (II) or ferrous






Sn4+
Sn2+
SnCl2
FeCl3
FeCl2
Hg22+
POLYATOMIC ANIONS
COVALENTLY BONDED, NON-METAL ANIONS
CO32- = CARBONATE ION
CN1- = CYANIDE ION
OXOANIONS: CENTRAL ATOM SURROUNDED BY OXYGEN
NO31NO21ClO1ClO21ClO31ClO41-
CO32HCO31-
NITRATE ION
NITRITE ION
1 LESS O
1 LESS O
HYPOCHLORITE ION
CHLORITE ION
CHLORATE ION
PERCHLORATE ION
CARBONATE ION
HYDROGEN CARBONATE ION
1 MORE O
56
NAMING IONIC COMPOUNDS
CATION ION + ANION ION = CATION ANION
Na1+ = SODIUM ION
Cl1- = CHLORIDE ION
Na Cl
SODIUM
CuBr
ZnO
CHLORIDE
COPPER (I) BROMIDE
ZINC OXIDE
Na2CO3
Fe2 (CO3) 3
SODIUM CARBONATE
IRON (III) CARBONATE
57
NAMING BINARY COVALENT COMPOUNDS
LESS ELECTRONEGATIVE ELEMENT FIRST:
RETAINS NAME
EXCEPTION H
MORE ELECTRONEGATIVE ELEMENT:
CHANGE END TO -IDE
MUST INDICATE NUMBER OF ATOMS WITH GREEK PREFIXES
1 = MONO
2 = DI
3 = TRI
4 = TETRA
5 = PENTA
6 = HEXA
7 = HEPTA
8= OCTA
9 = NONA
10 = DECA
DO NOT USE MONO FOR FIRST ELEMENT
DO NOT PUT TWO VOWELS TOGETHER
DECAOXIDE = DECOXIDE
58
NAME THE FOLLOWING:
NO
N2O
NITROGEN MONOXIDE
(NITRIC OXIDE)
DINITROGEN MONOXIDE
NO2
P2O5
H2O
CF4
NITROGEN DIOXIDE
DIPHOSPHORUS PENTOXIDE
DIHYDROGEN MONOXIDE
(WATER)
P4O10
NH3
CARBON TETRAFLUORIDE
TETRAPHOSPHORUS DECOXIDE
NITROGEN TRIHYDRIDE
(AMMONIA)
59
NAMING ACIDS
UNLESS DISSOLVED IN WATER -- COVALENT
HBr
BINARY:
HYDROBROMIC
HYDROGEN
HYDRO
BROMIDE
BROMIC
HF
HI
POLYATOMIC
ANIONS
H2CO
CO332-
HYDROFLUORIC ACID
HYDROIODIC ACID
CARBON
SO42- = SULFATE ION
SO32- = SULFITE ION
ACID
-ITE = OUS OR -ATE = IC
EXCEPTING S OR P
ATE
ION
IC ACID
H2 SO4 = SULFURIC ACID
H2 SO3 = SULFUROUS ACID






HBr
H2S
H2SO4
H2SO3
HNO3
HN



Contain Carbon and hydrogen
May contain oxygen, nitrogen, sulfur, and
occasionally other elements
Defined by # of carbon atoms, type of bonds
between the atoms, and other types of atoms
bonded to the carbons
All organic compounds
contain Carbon, but
not all Carbon
containing compounds
are organic!
Family of Organic
Compounds
Alkanes
Type of Bonds
between the Carbons
Single
Alkenes
Double
Alkynes
Triple
Overview
Hydrocarbons:
•alkanes
•alkenes
•alkynes
•arenes
66
# of 1
C
2
3
Pre- Meth Eth Prop
4
5
6
7
8
9
10
But
Pent Hex Hept Oct Non dec
Functional Groups in Hydrocarbons
R-H
•alkanes
•alkenes
•alkynes
Ar-H
•arenes
FG
FG
FG
FG
H
double bond
triple bond
ring
arenes
68
Functionally substituted derivatives
of alkanes
R-Der
Class
Example
R-OH
alcohol
CH3CH2OH
R-X
alkyl halide
CH3CH2Cl
R-NH2
amine
CH3CH2NH2
R2C
CR2
epoxide
H2C
(F,Cl,Br,I)
CH2
O
O
ether
CH3CH2OCH2CH3
nitrile
CH3CH2C
R-NO2
nitroalkane
CH3CH2NO2
R-SH
thiol
CH3CH2SH
R-O-R
R-C
N
N
69
Classes of cpds that contain a
carbonyl group
R-Der
Class
O
Example
C
O
O
aldehyde
CH3CH2COH
C
R CH
O
O
ketone
CH3CH2COCH3
H
C
R CR
O
O
ester
CH3CH2COOCH3
C
O
R COR
O
R COH
carboxylic
acid
O
CH3CH2COOH
C
H
O
70
Alkane: CnH2n+2
All carbons are sp3 hybridized
H
Methane (CH4)
H
H
4 C-H s bonds
C
H
H
Ethane (C2H6)
H
C
H
6 C-H s bonds
C
H
H
Propane (C3H8)
H
H
2 C-C s bond
C
H
H
C
C
H H
H
1 C-C s bond
H
8 C-H s bonds
H
71

CH4

C2H6

C5H12

C10H22
Alkane Nomenclature (IUPAC rules)
Unbranched Alkanes
methane
ethane
propane
butane
pentane
hexane
CH4
CH3
CH3
heptane
octane
nonane
decane
73



Drawn as geometric shapes where two lines
meet, a carbon is indicated
Lines between carbons show number of bonds
between carbon
Naming: use prefix cyclo- , then name according
to normal organic system
What’s so special about Benzene?
Benzene
(C6H6)