Starter: Quick Review
• How many minutes are in 2 weeks?
• Express the answer to 10.5m + 12.15m in
correct sig figs
• Express 525K in degrees Celcius
• The mass of a sample of salt is 20kg. The
density of the salt is 4g/cm3. What is the
volume of the sample of salt in mL?
As you come in,
The Materials:
• Paper and pencil for notes
•½ sheet of paper
• History timeline
• Pick up packet.
The Plan:
• Discuss your Unit One tests (return ASAP)
• Learn about basic atomic structure
Homework:
• Complete the Atomic Structure Numbers
Worksheet
NOTE: Models of the Atom, Isotopes, Atomic Mass
&, Atomic Structure Numbers Quiz on Monday
Starter:
Let’s Jog Your Memory
• So…what is an atom?
• Draw a diagram of an atom
labeling the following parts:
nucleus, electron cloud, proton,
electron, neutron
• Describe the 3 subatomic particles
(Ex: location, charge, mass, etc)
Back to the Reading
• Who theorized that all matter is composed of fire, air,
water, and earth?
• Name the famous Greek philosopher who agreed
with the theory described above.
• Name the scientist who established the Law of
Conservation of Matter.
• Name the famous Greek philosopher who disagreed
with #1 and said that matter could be broken down
into “atomos.”
• Who said that “All atoms of a given element are
identical.”?
Atomic Theory
• History of the Theory:
– Early ideas of the atom
• Democritus
• Aristotle
• John Dalton (pg. 56)
Atomic Theory
• History of the Theory:
– Early ideas of the atom
• Democritus - “atomos”; atoms exist
• Aristotle - atoms do NOT exist
• John Dalton (pg. 56) - 2000 years later; atoms
exist
– Matter is made up of atoms.
– Atoms are indivisible.
– Atoms of same (different ) elements are same
(different)
– LAW OF CONSERVATION OF MATTER
More Recent Atomic Theory
•JJ Thomson
• E. Rutherford
Found Electrons
through the cathode ray
experiment
Nucleus in gold foil
experiment
(Protons travel in different
directions when they hit
the nucleus)
Modern Atomic Theory
• Neils Bohr
•Schrodinger
First atomic model to
show Energy levels
Sublevels & orbitals
Subatomic Particles
Particle
Location
Charge
Actual Mass
Relative
Mass
Proton
Nucleus
+1
1.673x10-24
1
Neutron
Nucleus
None
1.675x10-24
1
Electron
Electron
Cloud (in
energy
levels)
-1
9.11x10-28
1
1840
Proton Significance
• Gives the atom its identity
• Equivalent to the atomic number
• Massive particle so adds to the atom’s
mass
• Gives the nucleus its positive charge
• Balances the negative charge of the
electrons
Neutron Significance
• Neutron glue that holds the nucleus
together
• Massive particle so adds to the atom’s
mass (mass number= p + n)
• Number can differ from one atom to
another giving isotopes
Electron Significance
• Responsible for chemical properties
• Forms ions when gained or lost, which
leads to a charge
Atomic Number
The picture is NOT
completely correct.
• Atomic # IS the
number of protons in
the atom. It is NOT
always the number of
electrons.
•Therefore, the atomic
# gives the atom its
identity...its name.
Atomic Number
• In isotopic notation, the atomic number
is shown in the lower left corner of the
element symbol.
• Example:
6C
Atomic NumberQuick Check
• If an atom is found to have 28 protons,
what is its identity?
• What is the atomic number of
phosphorus?
• How many protons does barium have?
• Show the following elements in “isotopic
notation”:
– Lithium, sodium, sulfur, lead
Atomic NumberQuick Check
• If an atom is found to have 28 protons,
what is its identity? Ni = Nickel
• What is the atomic number of
phosphorus? 15
• How many protons does barium have?
56
• Show the following elements in “isotopic
notation”:
– Lithium, sodium, sulfur, lead
Charge
• Charge = oxidation state
– Oxidation state is just a fancier way to say it.
• A charged atom results from an inequality
between protons and electrons in an atom.
• Which of those particles (protons or
electrons) are more likely to be gained or lost
from an atom? Why?
Charge Example
• Example: Bromine has 35 protons. It
often gains electrons to other atoms. If
Bromine gains an electron, the atom will
have 36 electrons. What will the charge
be?
– Answer: -1 charge
Charge...Now , you try
• Example: Calcium has 20 protons. It
often loses electrons to other atoms. If
calcium loses 2 electrons, the atom will
have only 18 electrons. What will the
charge be?
– Answer: +2 charge
Charge
• In symbolic notation, the charge is listed
in the top right corner of the element
symbol. If the charge is neutral, then
the corner is left blank.
– Question: What does Cl-1 means for the
amount of protons and electrons for a
chlorine atom?
– Answer: protons = 17 (don’t change),
electrons = 18 (gained one)
Charge
Quick Check
• What is the charge of sulfur when it
gains 2 electrons to the neutral atom?
• Write the symbolic notation to represent
an atom of aluminum that has lost 3
electrons leaving 13 protons and 10
electrons.
• How many protons and electrons are in
the following atom? Cu 2+
Charge
Quick Check
• What is the charge of sulfur when it gains
2 electrons to the neutral atom? S-2
• Write the symbolic notation to represent
an atom of aluminum that has lost 3
electrons leaving 13 protons and 10
electrons. Al3+
• How many protons and electrons are in
the following atom? Cu 2+ 29P, 27E
Mass Number
• Consider the subatomic particles.
Which TWO particles have enough
mass to matter?
• Mass number is always a whole
number...no decimals.
• Mass number is calculated by adding
the number of protons to the number
of neutrons.
Mass Number
• In symbolic notation, the mass number
is shown in the upper left corner of the
element symbol.
• Example:
12 C
6
**Important Equations**
Mass Number
Quick Check
• If a sodium atom has 11 protons and 12
neutrons, what is the atom’s mass
number?
• How many neutrons does a copper
atom with a mass number of 64 have?
• How many protons and neutrons are in
the atom represented with this symbolic
notation: 3216S
Isotopic Notation Summary
• Shorthand way to record the element symbol,
atomic number, charge, and mass number.
• With this information, you can deduce the
number of protons, neutrons, and electrons in
the atom being represented.
Mass #
Atomic #
X
Charge
Starter: Atomic Structure
• How many protons,
• Isotopes of the same
electrons
and
neutrons
element have
are in the following
different numbers of
atom?
_________ in their
atom but the same
58 Cerium-140
number of _______. Write the correct isotopic
• ________ do not
notation for the
affect the atom’s
element that has 26
mass but determine
protons, 30 neutrons,
the oxidation state.
and 23 electrons.
Take 10…Finish Up
• Complete at least 4 •
stations in the gallery
walk
• Isotopic Notation
must be complete
(atomic #, atomic
number)
• The assignment will
be turned in for a
•
grade today
If you finish early,
take out your Unit 2
review packet that
you received
yesterday and work
on the Atomic
Number WS
Please ask if you
have any questions
Atomic Structure: Part II
• Students will understand…
1. The difference between mass number
and atomic mass
2. How to calculate average atomic mass
and relative abundance
Blocks on the Table
• PROTONS give an atom its identity. They
are the ONLY subatomic particle that must be
identical from one atom to another. Neutrons
AND electrons can vary...
• SO, how can we create ONE box on the
periodic table to represent ALL atoms of an
element? We must represent AVERAGE
atoms. (That’s why the atomic mass has
decimals.)
Atomic Mass
• Atomic mass = the weighted average of
all of the types of atoms (isotopes) of
the element
– Must know the % abundance (how much of
it is found in nature relative to other
isotopes) and the mass number
– Check out the example!
Atomic Mass Example
• Copper exists as a mixture of 2 types of
atoms. The lighter copper has 29
protons and 34 neutrons, and it makes
up 69.17% of all copper atoms. The
heavier type has 29 protons and 36
neutrons. It makes up the remaining
30.83% of copper on earth. What is the
atomic mass of copper?
Atomic Mass Example
• Element Z exists in 3 isotopic forms.
The isotopic mixture consists of 15% Z16, 35% Z-17, and Z-18 makes up the
remaining percent. What is the atomic
mass of this element?
Relative Abundance
Calculation
• Element X has two naturallyoccurring isotopes with isotopic
weights of 10 and 12. You look on the
periodic table to find that its average
atomic mass = 10.5 What is th
relative and percentage abundance
of each isotopes?
Relative Abundance
Calculation
• Silver has two naturally-occurring
isotopes with isotopic weights of
106.90509 and 108.90470. What is the
relative and percentage abundance
of each isotopes?
Starter: AM Review
• Element M exists in 3 isotopic forms. The
isotopic mixture consists of 20% M-10,
50% M-15, and M-20 makes up the
remaining percent. What is the atomic
mass of this element?
• Chlorine has two isotopes. Chlorine-35
has an exact weight 34.968852 amu, and it
has a 75.77% abundance. The other
isotope has 36.965903 amu. What is the
atomic mass?
Isotope/Atomic Mass Lab
– You and your partner will analyze a sample
of the element Candium.
– Gather the data, and calculate the atomic
mass of candium.
– You can eat your sample at the end! 8-)
– Work on the new atomic mass calculations
ws at your desk when you are done.
Isotope/Atomic Mass Lab
– Important Information:
You can write on the sheet provided
Be sure to keep correct sig figs after
measuring the mass
Keep your candy on a paper towel if you
plan to eat them
Straighten up your lab area when you are
finished
Be sure to stay on task…the assignment is
graded!
Starter
• Hydrogen has two naturally-occurring
isotopes with isotopic weights of
1.007825 and 2.014102. What is the
relative and percentage abundance of
each isotope?
• True or False:
- Isotopes of an atom have different
numbers of protons.
- Although atoms are mostly empty space,
they still have mass.
Energetic Electron
• Electrons are energetic, and they exist on
energy levels.
• Quantum: specific amount of energy needed
to move from one energy level to the next;
energy levels are given principal quantum
numbers as a result
• When electrons change energy levels, energy
is absorbed and released.
• Light is sometimes visible when the energy is
released (Emission of Light)
Quantum Illustration
Quantum =
distance between
two energy levels
Principal Quantum
Number (n) =
begin counting
closest to the
nucleus
Quantum Illustration
Principal Quantum
number (n):
-Refers to the principal
energy level, which tells
you the amount of energy
the electron has
-The CLOSER the
electron is to the
NUCLEUS the LESS
energy it has
Quantum Leap Illustration
1. An electron from n=2
(ground state) can absorb a
quantum of energy and
jump to n=3 (excited state).
2. Excited state is temporary.
3. The electron will soon
release the quantum and
fall back from the higher
level to ground state.
4. EMISSION OF LIGHT can
occur and the released
energy will travel as a wave.
Electromagnetic Spectrum
(All energy waves fall into one of these
categories.)
Electromagnetic Spectrum
Let’s see if you get it…wavelength vs frequency
Calculating the
Emission of Energy
• Two Equations to calculate the energy:
1. Speed of light = wavelength x frequency
c = λν
c = 3.0 x108 m/s (speed of light is constant)
2. Energy = Planck’s constant x frequency
E = hν
h=6.626x10-34 Jsec (Planck’s constant)
Finding a Connection
Look at the two equations. What variable
do they have in common?
A.) Speed of light (c)
B.) Wavelength (lambda)
C.) Frequency (nu)
D.) Energy (E)
Electromagnetic Wave
Calculations
• So, if I know the _______ of a wave,
then I can calculate its wavelength AND
its energy.
Energy Practice Problem:
If the wavelength is 0.001 meters, then
what is the frequency of the wave?
A.) 300,000 Hz
B.) 3.0x1011 Hz
C.) 3.33x10-12 Hz
D.) 6.626x10-37 Hz
Energy Practice Problem:
If the wavelength is 0.001 meters, then
what is the energy of the wave?
A.) 1.99x10-22 J
B.) 2.21x10-45 J
C.) 1.99x1046 J
D.) 6.626x10-37 J
Energy Practice Problem:
If the frequency is 7.0x1013 Hz, what is
the wavelength of the wave? What is
the energy of the wave?
A.) 4.29x106 m; 4.63x1020 J
B.) 2.33x105 m; 1.55x10-28 J
C.) 4.29x10-6 m; 4.63x10-20 J
D.) None of these
Starter:
• When do electrons emit light?
• If an electron moves farther from the
nucleus what happens to its energy?
• If the frequency is 4.0x1012 Hz, what is
the wavelength of the wave? What is
the energy of the wave?
Electron Configuration
• Electrons are arranged into different
levels within the electron cloud based
on their energy
• In order to arrange the electrons, you
must first know how many there are
Hoya Hotel…The analogy
• Hotel = electron cloud
• Floors = principal energy levels
– 1-7 COEFFICIENTS
• Rooms = sublevels (consist of
orbitals)
– s = sphere, p = dumbbell, d & f
• Guests = electrons
– Up and down = direction of spin
Hoya Hotel
Rooms (Sublevels) available:
S: Single room, has only one bed (sleeps 2)
P: Prestige room, has three beds (sleeps 6)
D: Deluxe room, has five beds (sleeps 10)
F: Fabulous room, has 7 beds (sleeps 14)
So…how can I remember
these levels
• The DIAGONAL RULE will help you to
determine the order for placing the
electrons into their sublevels
Lets practice…Write the electron
configuration for the following
1. Oxygen 2. Bromine
Noble Gas Notation
• Noble Gas Notation is a shorter way to
write out electron configurations
• Start the configuration at the noble gas
just before the atom and complete the
normal electron configuration
• Lets look at oxygen and bromine
again…
Periodic Table Labeling
S block: blue
d block: red
P block: yellow
f block: green
Periodic Table Labeling
S block: blue
d block: red
P block: yellow
f block: green
What does this all mean?
• Let’s analyze the configuration of
magnesium.
–
–
–
–
Energy levels
Sublevels
Electrons
Valence level and electrons
• What can I NOT find represented in the
electron configuration?
– Orbitals
– Pairing
Hoya Hotel
• Terms of Occupation:
– Aufbau Principle: Each room/bed on the lower
floors must be occupied before moving to a higher
floor.
– Pauli Exclusion: A maximum of two guests may
occupy a bed. Guests must sleep head to foot.
– Hund’s Rule: Single guests must occupy separate
beds in a room. No pairing occurs unless no
empty beds exist.
Orbital Diagrams
• Visual representation of electron cloud
• Shows everything that electron configuration
shows PLUS orbitals & pairing
– How to Draw an Orbital Diagram
• Write the electron configuration first.
• Draw the “beds” (orbitals) under each room.
• Put the electrons in the “beds.”
Let’s practice...
• Write the electron configuration for:
– Fluorine
– Magnesium
– Palladium
• Write the noble gas notation and orbital
diagrams for the elements above.
Starter:
• Write the correct electron configuration,
noble gas notation, and orbital diagram
for Barium
Which of the rules for filling orbitals does
the picture to the right of the board
violate?
Flame Test Lab Instructions
• You will rotate between the stations from
1 to 6
• Dip the wire into the solution and place in
the fire. Observe the color.
• In your data table, write a detailed
description of each color you see
• These descriptions will help you to
determine your unknown
Analyzing Orbital Diagrams
& Stability of Atoms
• Electrons are responsible for the chemical
properties (personalities) of atoms.
– STABLE = All orbitals (beds) are full.
– PRETTY STABLE = All orbitals (beds) are full
OR half-full.
– UNSTABLE = Empty orbitals (beds) exist.
NOTE: If an atom has to have an empty orbital, it is
best for the empty orbital to be on the valence energy
level so that it might be filled by electrons from a
nearby atom.
Analyzing Stability
Draw the orbital diagram of sodium.
Is sodium stable, pretty stable, or
unstable?
A.) Stable
B.) Pretty Stable
C.) Unstable
Analyzing Stability
Draw the orbital diagram of chromium.
Is Cr stable, pretty stable, or unstable?
A.) Stable
B.) Pretty Stable
C.) Unstable
Practice Analyzing Stability
1. Draw the orbital diagram of sodium. Is
sodium stable, pretty stable, or
unstable?
– Answer: UNSTABLE; Sodium has one half-full
orbital, but it’s third energy level has three empty p
orbitals.
2. Draw the orbital diagram of chromium.
Is Cr stable, pretty stable, or unstable?
–
Answer: UNSTABLE; chromium has one empty
orbital.
Exceptions to the Rules
• Exceptions to Aufbau principle:
– Chromium and Copper columns ONLY
– Stability of filled and half-filled sublevels
• Arrangement’s impact on bonding
Atomic Emission Spectra
•
•
•
•
Unique to each element
“Fingerprint”
Used to identify unknowns
Shows all wavelengths of visible light
given off by an atom
• Flame Test Lab
Starter:
• Write the correct electron configuration,
noble gas notation, and orbital diagram
for the following atoms:
1. Calcium
2. Silver
True or False: Emission of light occurs
when an electron absorbs energy and
jumps from the ground state to a higher
level.