ATOMIC
STRUCTURE
ATOMIC MASS UNIT
(a.m.u.)
A system of mass measurement used for
extremely tiny particles (such as the
parts of an atom)
1 a.m.u. = 1.66 x 10-24g =
.00000000000000000000000166 g
Which would you rather write?
NUCLEUS
The positively charged “center” of an atom
Virtually ALL of an atom’s mass is located in the nucleus
Composed of protons and neutrons
PROTONS
Positively charged particles that are
located in the nuclei of atoms
Mass = 1 atomic mass unit (a.m.u.)
NEUTRONS
Uncharged particles located
in the nuclei of atoms
Mass = 1 a.m.u.
ELECTRONS
Negatively charged particles that surround (orbit)
the nuclei of atoms
Electrons have virtually NO mass: Mass = 0 a.m.u.
Let’s Synthesize!
Bohr Model of Oxygen
Nucleus
Number of
Protons
Electron
Energy
Levels
Number of
Neutrons
Smaller particles of matter....Quarks
Scientists hypothesize that electrons are not make up of
even smaller particles, however, protons and neutrons
are!
The particles are called quarks.
At the present time, scientists believe that three quarks
make up a proton, and three quarks make up a neutron.
The Tevatron
The Tevatron is the most powerful
proton-antiproton accelerator in the
world. It accelerates beams of
protons and antiprotons to
99.99999954 percent of the speed of
light around a four-mile
circumference. The two beams
collide at the centers of two 5,000ton detectors positioned around the
beam pipe at two different locations.
The collisions reproduce conditions
in the early universe and probe the
structure of matter at a very small
scale.
Finding the sixth quark took a team of nearly 450 scientists several years.
The collisions of protons with oppositely charged particles at high energies were
necessary to produce the sixth quark.
This sixth quark is typically referred to as the "Top Quark".
ISOTOPE
Atoms of the same element that have
different numbers of neutrons
Label the diagram of the atom
Click here
for the
answer
Nucleus
Protons
Neutrons
Electrons
The structure of an atom
Nucleus
Electrons
Neutrons
Protons
Click here
to go
back
Atomic Number equal the number of protons and determines the element’s place in
the Periodic Table.
Atomic Weight equals the weight of an atom compared with the weight of an atom of
carbon 12.
Atomic Mass or Mass Number equals the number of neutrons and protons. This
number is very close to the atomic weight.
Electrons are orbiting the nucleus in a specific order.
Periods and Groups on the P. T.
Read the handout
"Supersize the Atom".
Complete Periodic Table Practice sheet for
homework.
Finish the Element Challenge Sheet!
Element
Symb
ol
Atomi
c #
AtomicMas
s
Metal, nonmetal,
metalloid
Characteristic and uses
1.
Hydrogen
H
1
1.008
non metal
most abundant element in U
welding, fuel cell
2. Carbon
C
6
12.011
non metal
diamonds,graphite, LIFE!
3. Oxygen O
8
15.999
non metal
4. Silicon
Si
14
28.086
non metal
5. Iron
Fe
26
55.845
metal
6. Krypton Kr
36
83.80
non metal
7.
Chlorine
Cl
17
35.453
non metal
8.
Pu
Plutonium
94
(244)
metal
9. Lead
Pb
82
207.2
metal
10. Silver
Ag
47
107.363
metal
Protons, Neutrons and Electrons
Protons and neutrons are located inside the nucleus.
Electrons are located in shells or energy levels
and orbit or move around the nucleus.
Energy Level
Shell Letter Electron
Capacity
1
K
2
2
L
8
3
M
18
4
N
32
5
O
50
6
P
72
3 Rules to Remember!
1. # of Protons = # of Electrons
P=E
2. Atomic number equals number of protons
3. Atomic mass or mass number equals number of protons
and number of neutrons
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Electron Configurations
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Name________________
Symbol_______________
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
# of Neutrons_________
Pre 1980 pennies needed for Friday.
Bring 2 pennies in.
WITHOUT USING A PERIODIC TABLE, COMPLETE THE
FOLLOWING AND DRAW THE ELECTRON CONFIGURATION.
Name________________
Symbol_______________
Ca
Atom Number_________
Atom Mass___________
#of Protons___________
# of Electrons_________
20
# of Neutrons_________
20
G
L
N
U
F
D
T
M
A
Q
S
P
H
V
X
J
C
B
K
Y
R
I
O
W
E
Gold and Silver Pennies (or How to be an Alchemist) Lab
Safety: This lab requires safety goggles!! The strong heated base can severely
damage your eyes and skin. Much caution is required during the entire lab!!
Solid sodium hydroxide or
solutions of sodium hydroxide
will cause chemical burns ,
permanent injury or scarring if it
contacts unprotected human, or
other animal, tissue. It will cause
blindness if it contacts with the
eye. Protective equipment such as
eye protection should always be
used when handling the material or
its solutions.
Gold and Silver Pennies (or How to be an Alchemist) Lab
Safety: This lab requires safety goggles!! The strong heated base can severely damage your eyes and
skin. Much caution is required during the entire lab!!
Materials: Strong base solution (NaOH), zinc powder, alcohol burner and stand, 100 ml beaker, balance
and weighing paper, graduated cylinder, forceps, beaker tongs, crucible tongs, two pennies dated earlier
than 1980 per person (total 4 pennies)
Procedure for Part I:
Measure 25 mL of base solution in a graduated cylinder and pour it into the beaker.
Light the burner and set it under the stand.
Put the beaker on the stand and start heating it.
Measure 1.0 g of zinc powder on a balance, using the weighing paper technique.
Pour the zinc powder into the strong base.
Put one copper penny PER PERSON into the hot base solution.
Stir the pennies for 3 minutes with forceps.
WARNING: Do not let the solution boil. Don’t breathe the fumes. Be careful to not spill the
base solution!
Remove the pennies with a forceps and rinse in cold running water for a count of 20 seconds.
Remove caked-on zinc with fingers. Set your “silver” pennies aside.
Procedure for Part II:
1. Put one copper penny per person again into the hot base.
2. Stir the pennies again for another 3 minutes.
3. Take out the pennies and rinse in cold water again for 20 seconds.
Dry the pennies, making sure the caked on zinc is gone. Use a crucible tong to hold one penny at a time in
flame of your burner. Do this until the penny turns “gold”. Don’t leave your pennies in the flame too long or t
will not be shiny. Each person should now also have a “gold” penny.
Clean up: Wear your goggles. Pour the base solution down the sink with plenty of running water. Rinse you
graduated cylinder. Wipe up your lab area.
Answer the questions on the back to complete this lab.
Alloy
A homogeneous mixture or solid solution
of two or more metals.
Examples:
magnelium - magnesium and aluminum used for making
balances.
brass- copper and zinc
bronze- copper and tin
sterling silver- copper and silver
solder- tin and lead
Materials with a Past
1. What is an alloy?
2. Why is an alloy a homogeneous mixture?
3. What is brass?
4. What is bronze?
5. Name two more alloys containing copper.
6. What is an amalgam?
7. What do all steel alloys have in
common?
Questions:
1. What are the modern abbreviations for the above elements?
Zinc _________ Copper _______ Tin __________ Lead __________
2. How are elements different from mixtures? ___________________________________
___________________________________________________________________________
3. How many different elements does it take to make a mixture? _________________
4. Would this drawing represent an element or a mixture? _______________________
5. How many atoms are drawn above (see C.) for each mixture?
Brass ____________ Bronze _____________ Solder ______________
6. How many different elements does it take to make each of the alloys drawn above? Brass __________ Bronze __________ Solder
___________
7. What element coats the “silver” penny you made in lab? ____________________
8. What alloy coats the “gold” penny? ____________________________
9. Draw an alloy of the elements zinc, copper, and tin made up of ten total atoms, using the Dalton Models above.
10. Sterling silver is an alloy of silver and copper. Make up a drawing of a sample of sterling silver, using 10 atoms. (You’ll have to think of a wa
represent silver atoms first.)
An ALLOY is a mixture of metals. They are mixed when the metals are
melted together, but there is NOT a chemical reaction between the
atoms. Some common alloys are in the table below. Alloys have very
different properties than the individual metals that make them up.
Alloy
Metals
Uses
Brass
Copper, zinc
Hardware,
musical
instruments
Bronze
Copper, tin
Art, buildings
Pewter
Tin, copper,
bismuth,
antimony
Art, dinnerware,
candlesticks
Solder
Lead, tin
Connecting metal
pieces together
Stainless steel
Iron, chromium,
nickel
Silverware,
knives
1. How many different elements does it take to make an alloy?
2. How many elements are in the alloys…
Brass? ___ Bronze? ___ Pewter?___ Stainless Steel? _____
3. Stainless steel is what your silverware and knives are made of. Why is the alloy
stainless steel better for silverware than pure iron?
4. What ALLOY coats the “gold” penny you made in lab? Hint- you melted one metal
into another metal.
_____________________
5. A copper atom has ____ protons in its nucleus. It has _____ electrons outside its
nucleus. It also has ____ neutrons in its nucleus. A copper atom’s atomic number is
______ and its mass number is _________.
ALCHEMY was practiced back in the Dark Ages,
before there was “real” science. Alchemists had two
goals: 1 - to discover a substance that could make
them live forever, and 2 - to figure out how to turn
cheap metals such as lead and zinc into valuable
gold.
Imagine trying to turn lead into solid gold! They were
never successful of course. But, they did learn very
much about properties of metals and reactions, even
if they didn’t really understand the science behind it.