Transcript Atomic Theory Powerpointx

Unit 3: Atomic Theory &
Periodicity
th
Monday, October 24
LEARNING OBJECTIVE A: Atomic
Warm-up: Pick up the
Learning Targets
Highlight the quiz and test
dates and copy them into
your planner
Information
1. State the location & charge of
each subatomic particle within
the atom
2. Use the periodic table to
determine the number of
protons, neutrons, and electrons
Independent Practice #1 is
in an atom of an element
due on 10/27
3. Define atomic number as it
relates to subatomic particles
Video
Take careful notes on the video, think about the
learning targets as you are watching
Video Wrap up
•What are the 3 common particles in an atom?
•What 2 particles are in the nucleus?
•If an atom were expanded to the size of a stadium what size
would the nucleus be?
•What’s between the atom’s nucleus and the electrons?
•Where is the majority of the mass in an atom?
In your notes
Make a table in your notes to complete with the information you have learned.
Particle
Location in
atom
Charge
Mass in AMU
BOHR MODEL
A Bohr Model is a simplified
version of what an atom looks
like. The protons and neutrons
are located in the nucleus and
the electrons are in “shells” or
rings around the nucleus
You draw a Bohr Model by
placing two electrons maximum
in the shell closest to the
nucleus and a maximum of
eight electrons in each of the
other shells.
Check in
•How many protons does Iodine (I) have?
•How many protons does Tungsten (W) have?
•Which subatomic particle has a negative charge?
•What is the mass of one neutron?
•Where in an atom are electrons located?
•Draw a Bohr Model of a neutral atom of Sodium (Na)
Information from the Periodic Table
Number of Protons: same as atomic number
Mass Number: listed as an AVERAGE on the periodic table. Calculated as number of protons plus the number of
neutrons for individual atoms.
Number of electrons in a neutral atom: same as number of protons
Isotope/Atomic Notation:
Tuesday, October 25
LEARNING OBJECTIVE A: Atomic Information
Warm-up: How many protons does Bromine (Br)
have? How do you know? Write the atomic/isotope
notation for Bromine-81
Independent Practice #1 is due on Friday 10/27
Answer to Warm-up
Warm-up:
1.
How many protons does Bromine (Br)
have?
2.
How do you know?
3.
Write the atomic/isotope notation for
Bromine-81
Answer:
1.
Bromine has 35 protons
2.
The atomic number for Bromine is 35. The
atomic number is equal to the number of
protons.
3.
The isotope/atomic notation is:
Isotopes
Each table will need a sheet of Model 1 and each member of your
group will need their own Isotopes packet and a periodic table.
Choose your roles. Facilitator will appoint a reader for the activity.
Spokesperson will appoint a clean up person for the activity.
Work through carefully, making sure you reach consensus on each
question. Switch your cup to yellow at stop signs (pretend they are
yield signs ) but keep moving.
Wednesday, October 26
LEARNING OBJECTIVE
I will be able to calculate average atomic mass.
1.
WARM UP
How many neutrons are in…
2.
What are isotopes?
A.
B.
C.
Uranium-235 (atomic number 92)
Lead-207 (atomic number 82)
Hydrogen-3 (atomic number 1)
Check in from Tuesday
today
Relative Abundance Lab
Wednesday 10/26 Exit Slip
Learning Objective
I will be able to calculate average atomic mass.
Exit Questions
Why is average atomic mass so important it was
included in the periodic table?
Thursday - October 27
Learning Objective B: Isotopes and Relative Atomic Mass  Connecting back to
Learning Objective A- Atomic Information & Moles and Mass!
Warm-up: Have Independent Practice Number 1 out
REMINDER: Quiz 1 is TOMORROW
Average Atomic Mass
How do we calculate average atomic
mass using abundancy?
1. The average atomic mass of nitrogen is 14.0067 amu. Predict which
isotope listed below is most abundant in nature
Wrap Up
◦ a. Nitrogen-13
◦ b. Nitrogen-14
◦ c. Nitrogen-15
2. A certain element was originally named “muriaticum” by its
discoverer. This element exists on Earth as a mixture of two isotopes.
The most abundant isotope (75.76%) has a mass of 34.9689 amu; the
other isotope (24.24%) has a mass of 36.9659 amu. Calculate the
average atomic mass and identify the element by its modern name.
Table Swap
Each table has a specific learning goal listed. Your group will be solving
and writing questions around the learning goal you have been
assigned.
We will rotate (Table 1 Table 2  Table 3 … etc) every 4 minutes
There is a starter problem on the table for your group to solve – you
must show all your work!
Once you have solved the problem you need to write a similar type of
problem for the next group. Include the answer so they can check
their work.
Answers
1.B Nitrogen-14
1.(0.7576)(34.9689 amu) + (0.2424)(36.9659) = 35.45
amu Chlorine
Friday – October 28
Learning Target C: Half-Life
Independent Practice #2 is Due Tuesday 11/1/16
Warm-up: Be ready for the quiz!
You will have 15 minutes to take the quiz
Quiz
Clear your table of everything except something to
write with, a calculator, and a periodic table.
When you are done – pick up independent practice
#2 from the front table.
Independent Practice #2 is Due Tuesday 11/1/16
Monday,
st
October 31
Today you will work on a half-life lab
1. Complete the first page of the lab as a pair. (2 per table)
2. Graph your data. Compare with the other pair at your table.
3. Work together through the first handout.
4. Get the second portion (everyone has their own) and work
through them as a group.
Monday,
st
October 31
Target C: Half-Life
Warm-Up: Have your half-life extension
problems from Friday out and some note paper
out to take notes on 
Plan for today – Monday 10/31
Review Quiz #1
Half-Life Calculations & Practical Examples
Begin talking about fission & fusion
Tuesday November
st
1
Fission & Fusion
Learning Targets
◦I can compare the energy outputs of fission and fusion reactions
◦I can compare the energy outputs of fission and fusion to other
energy transformations
Warm-Up:
A specific radioisotope takes 600 minutes to decay to 12.5% of its
original mass. What is its half life?
Plan for today – Tuesday 11/1
Review half-life
Fission & Fusion handout (complete)
Discussion Independent Practice #2
Review for Wednesday Quiz
Nuclear Reactions – some rules for
fission & fusion
1. Mass must be conserved: atomic mass of the reactants must be
equal to the atomic mass of the products
2. Protons must be conserved: the total number of protons that go
into the reaction (on the reactant side) must be the same total
number that comes out of the reaction (on the product side)
3. If the atomic number of an element changes, the element itself
changes
Fission & Fusion (from your note packets)
Fission:
Fusion:
A large nucleus is hit by
something and splits into many
smaller nuclei
Two smaller nuclei are
combined to make a larger
nucleus
Usually Uranium-235 is hit by a
neutron
Recognizable because the
largest mass will be on the
Recognizable because the largest
reactant
side
of
the
mass will be on the reactants
equation.
side of the equation
Fission
Wednesday November
nd
2
Warm- Up:
Clear your table for the Quiz, you need a periodic table, a
calculator maybe, and something to write with
Independent Practice #3 Due Monday 11/7
Learning Target D: Electron Configuration
Boarding House Model
What do the symbols mean?
= A person
= Bunk bed for 2 people
The big number (1, 2, 3) = The floor number
s = The sunny room
p = The pink room
The exponents (1,2,3,4,5,6) = How many people are in that room on that floor
Rules for filling the boarding house
(generated by our class)
1. Start adding people on the lowest floor first
2. 2 people can fit in each bunk bed
3. You can not put someone in a top bunk until all of the bottom bunks in that room are full
4. No one can sleep in the kitchen
5. You must fill all the bunk beds on the current floor before you can move to the next highest
floor
6. Sunny room on that floor must be filled before pink room on that floor
7. People are added gradually, no one leaves
8. Add people from left to right in the room
What is the manager code for these three
situations?
A
B
C
Thursday November
rd
3
Learning Target D: Electron
Energy Levels
Warm-up: Write the managers
code for the following boarding
house
Warm-up Solution
What do these symbols
represent?
What do these symbols
represent?
Orbital (a bunk bed)
A single electron spinning up (one
person)
Two electrons with opposite spins (two
people – one in bottom bunk one in top bunk)
A sublevel (a room)
Electron configuration (managers code)
Orbital Diagrams & Electron
Configurations
Orbital Diagrams
o Explain how electrons are arranged within
the atom
o Show the order in which electrons are placed
in orbitals
o Use boxes to represent orbitals
Electron Configuration
Short hand to show how many electrons are in
an atom and at which energy level they will be
found.
Electrons in Orbital Diagrams
To place electrons in orbital diagrams, electrons:
oare represented by arrows and the direction of the arrow is
used to represent electron spin
ofill orbitals in order of increasing energy beginning with 1s,
then 2s and 2p, then 3s and 3p
Electrons in Orbital Diagrams
Orbitals can hold a maximum of two electrons.
Within sublevels that contain multiple orbitals, one electron is placed
in each orbital with parallel spins before the electrons are paired.
Electron Configurations
Chemists use a notation called the electron configuration to indicate placement of electrons in an
atom.
The lowest energy sublevel is written first, then sublevels with increasing energies.
The number of electrons in each sublevel is written as a superscript.
Period 1: Hydrogen and Helium
The 1s is written first; it has the lowest energy.
Period 2: Lithium to Neon
Period 2 begins with lithium, which has three electrons, 1s2 2s1.
After the 2s is filled, the 2p orbitals are filled.
One electron is placed in each p orbital before they are paired.
An abbreviated configuration uses a noble gas in brackets to represent the filled electron
configuration of that noble gas.
[He] 2s1
Period 2: Lithium to Neon
Period 2: Lithium to Neon
Guide to Drawing Orbital Diagrams
Sample Problem
Draw the orbital diagram for nitrogen.
Step 1
Draw boxes to represent the occupied orbitals. Nitrogen has an atomic number of
seven, which means it has seven electrons. Draw boxes to represent the 1s, 2s, and 2p
orbitals.
1s
2s
2p
Sample Problem
Draw the orbital diagram for nitrogen.
Step 2
Place a pair of electrons in the last occupied sublevel in separate orbitals. We
place the remaining three electrons in the 2s orbitals.
1s
2s
2p
Sample Problem
Draw the orbital diagram for nitrogen.
Step 3
Place remaining electrons with opposite spins in each filled orbital. First we
place a pair of electrons with opposite spins in the 2p orbitals, with arrows in the
same direction.
1s
2s
2p
Period 3: Sodium to Argon
[Ne] is used to represent 1s2 2s2 2p6.
Period 3: Sodium to Argon
Learning Check
Draw the abbreviated orbital diagram for aluminum:
[Ne] 3s2 3p1
Solution
Draw the abbreviated orbital diagram for aluminum, [Ne] 3s2 3p1.
1.
The preceding noble gas is Ne; we use this
to represent 1s2 2s2 2p6.
2.
Fill the 3s, and add the last electron to the
3p sublevel.
[Ne]
3s
3p
Friday, November 4th
Learning Target E: Ions
Guiding Question: How are ions made from neutral atoms?
Warm-up:
Write the ground state electron configuration for a neutral
atom of Chlorine
Warm-up Solution
Chlorine has 17 electrons in a neutral state (atomic number of 17 = 17 protons, to be
neutral it would need 17 electrons)
Ground state electron configuration for a neutral atom of Chlorine:
1s22s22p63s23p5 or [Ne] 3s23p5
How should I check my work?
Each s sublevel can only have two electrons
Each p sublevel can only have a maximum of 6 electrons
The exponents should add up to 17.
Chlorine is in the 3rd row of the periodic table and the p5 column so the electron
configuration should end in 3p5
What is an ion?
An ion is a charged particle. Instead of being neutral, our ion has either a
positive or a negative charge
Ions are formed when atoms gain or lose electrons.
Positive ions are called cations. They are formed when a neutral atom loses
electrons.
Negative ions are called anions. They are formed when a neutral atom gains
electrons.
Metallic atoms tend to lose electrons to form positive ions/cations.
Nonmetallic atoms tend to gain electrons to form negative ions/anions.
How do we calculate the charge on an
ion?
The charge on an atom or ion is equal to its number of protons minus its
number of electrons
Charge = (# of Protons) - (# of Electrons)
Example:
An atom with 17 protons and 18 electrons has a charge of -1
Cl1-
How do we indicate that an element is
in its ion form?
Charge is listed on the top right side of the
atomic/isotope notation: Cl1Ion configuration includes the gained or lost electrons
For an ion of chlorine the ion configuration would be:
1s22s22p63s23p6 or [Ne] 3s23p6 or [Ar]
Ionization wrap up
Ionization is losing or gaining electrons to get to a full
valence shell. If an element has less than 4 electrons in
the valence it will lose electrons, if it has more than 4
electrons it will gain electrons.
This is called the octet rule. Elements want to have 8
valence electrons
Oxidation & Reduction
If an element loses electrons it is OXIDIZED
If an element gains electrons it is REDUCED
LEO the lion says GER
LEO= Loss of Electrons is Oxidation
GER= Gain of Electrons is Reduction
Monday November 7, 2016
Learning Target: Electron Dot Diagrams
& Ion Configuration
Warm-up: How many valence electrons
does a neutral atom of Nitrogen-15 have?
How do you know?
Warm-up
Warm-up: How many valence electrons does Nitrogen have? How do you know?
How many ways can you show that Nitrogen has 5 valence electrons?
1.
Bohr Model
2.
Orbital Diagram
3.
Electron Configuration
4.
What group it is in on the periodic table
Ionization – review from Friday
Ionization is losing or gaining electrons to get to a full
valence shell. If an element has less than 4 electrons in
the valence it will lose electrons, if it has more than 4
electrons it will gain electrons.
This is called the octet rule. Elements want to have 8
valence electrons
Oxidation & Reduction
If an element loses electrons it is OXIDIZED
If an element gains electrons it is REDUCED
LEO the lion says GER
LEO= Loss of Electrons is Oxidation
GER= Gain of Electrons is Reduction
The ion charges that form are called “oxidation states”
For Today
Finish Electron Configuration, Ions, Subatomic
Particle
Review Independent Practice #3
Start Lewis Dot Diagrams
Tuesday, November
th
8
Plan for today:
Quiz #3
Lewis Dot Diagrams
Pick up Independent Practice #4 Due 11/19
Quiz
Clear your table except for a periodic table, something to write
with, and a calculator.
You will have 15 minutes for the Quiz. SHOW ALL YOUR WORK.
Reminder for Throwback question - the formula for Molarity
(concentration) is:
Molarity = moles / liters
Lewis Dot Diagrams
Work through the Lewis Dot Diagrams activity as a group, checking in
frequently to make sure you have reached a consensus.
When you are finished please gather the Lewis Dot Diagram (Dot Diagram #2)
handout from the front. One per group.
Cut out the elements and distribute them evenly among your group members.
Write the dot diagram configuration for all of them.
When you are done, look for patterns in the diagrams by organizing them as a
group.
What do you notice?
Wednesday November
th
9
Learning Target: Trends in Reactivity
You will need goggles, something to write
with, your notes, and the lab handout.
New Vocabulary: Group & Period
On your periodic table you have Groups & Periods
the horizontal rows are called periods (energy
levels)
the vertical columns are called groups (families)
The main groups are numbered from 1A to 8A going
from left to right
The block in between Group 2A and Group 3A is
where the transition metals are placed
Why does this matter?
Elements in the same group have similar chemical
properties – however, their reactivity can vary.
Your lab today will help you to answer the question:
How does the position of an element in a column on
the periodic table affect the reactivity of that
element?
Lab
Write your hypothesis to answer the testable question
Perform your experiments to test your hypothesis (you
might want to use a flashlight to see the reaction better!)
Record your data (you should see a minimum of 4
reactions)
Write up your procedure and your conclusion
Due tomorrow: procedure, data, conclusion (1 per group)
Thursday November
th
10
Properties of Elements – you will need a jacket
if you do not have one, we’re going outside near
the end of class.
Monday - November 14
Learning Target H: Discuss the properties of Alkali Metals
Learning Target G: Describe the trend in atomic radius as you move from
left to right and top to bottom of the periodic table
Warm-up: Draw the Lewis Dot Diagrams for the following metals:
◦Lithium
◦Sodium
◦Potassium
Some new terms!
Ionization Energy: The amount of energy needed to remove an electron
from an atom
First Ionization Energy: The amount of energy needed to remove the MOST
loosely held electron from an atom in its ground state
Electronegativity (sometimes called Electron Affinity): The energy change
for the process of adding an electron to an atom. How much an atom would
like to gain an electron.
Atomic Radius: Distance from the nucleus to the outermost energy level
(valence electrons)
Properties of Groups Poster
Your table group will make a poster that explains the properties of 1 of the periodic groups.
Your poster should have:
The name of the group
The number of the group
How many valence electrons elements in the group have
What elements make up the group
At least one fact about the group
Trends in atomic radius, electronegativity, and first ionization energy
The atomic radius, electronegativity, and first ionization energy of your FIRST
element in the group
At the end of the class we will rotate around and complete our notes using the posters
Learning Target: Define the terms “period” and “group” as they relate
to the periodic table
Plan for Today
Pick up and complete the periodic table handout from the front of
the class
1a & 2a
Periodic Table Groups - Alkali Metals - Group 1
Alkali metals are elements found in group 1 of the Periodic Table. Alkali metals are soft, malleable, ductile, and are
good conductors of heat and electricity. They have Low melting and boiling points compared to most other metals.
The names of these elements are Lithium, Sodium, Potassium, Rubidium, Cesium and Francium. They are silvercolored when pure and soft. Elements classified as Alkali Metals are very reactive metals that do not occur freely
in nature.
Periodic Table Groups - Alkaline Earth metals - Group 2
Alkaline Earth metals are the elements in group 2 of the Periodic Table. The chemical symbols identify the element
names. The alkaline earth metals are silvered colored, soft metals. Elements classified as Alkaline Earth Metals are
all found in the Earth’s crust, but not in the elemental form as they are so reactive. Instead, they are widely
distributed in rock structures. Alkaline metals are usually shiny solids that conduct heat or electricity and can be
formed into sheets.
7a & 8a
Periodic Table Groups - Halogens - Group 7a
The 5 elements classified as "Halogens" are located in Group 7a of the Periodic
Table. They are non-metals with low melting and boiling points. They have
colored vapors and are poor conductors of heat and electricity. The elements
classed as Halogens are Fluorine, Chlorine, Bromine, Iodine and Astatine.
Periodic Table Groups - Noble Gases - Group 8a
The Noble Gases are in Group 8a of the periodic table. All of these gases are
found in air and make up around 0.96% of the atmosphere. They are very unreactive and colorless gases The 6 elements classed as noble gases are Helium,
Neon, Argon, Krypton, Xenon and Radon.
Tuesday November 15
Learning Target: Periodic Trends – atomic radius, valence electrons,
electronegativity, ionization energy
Warm-up: Write the electron configuration for a neutral atom of Carbon. Circle
the final orbital notation in your configuration.
Example: The electron configuration for a neutral atom of sulfur is:
1s22s22p63s23p4
Periodic Trends
Orbital Notation & The Periodic Table
◦ Assessment #1
◦ If correct  Go on to Coulombic Attraction
◦ If not yet correct  Electron Configuration Practice Sheet
Coulombic Attraction
◦ Assessment #2
◦ If correct  Go on to Periodic Trends
◦ If not yet correct  Review Coulombic Attraction, write a
list of rules for identifying strength of Coulombic
attraction
Periodic Trends (model 1 is a separate
sheet – make sure you get both  )
During each activity:
◦ Use the post-it notes in your pencil boxes
to make a claim, provide evidence, and list
a scientific reason for the 4 periodic trends
we are discussing today.
◦ A sample claim format has been listed on
the board for you!
◦ Each group should make at least 1 claim, 1
evidence, and 1 reason to place on the
poster on the front table. That is 3 post-it
notes total 
Wednesday 11/16
Guiding Question:
What is the scientific
reasoning for the trends
found on the periodic
table?
Goal:
Complete all three assessments
Turn in assessments and
completed independent practice by
the end of class
Prepare for tomorrow’s quiz
What trends did we observe on the
periodic table?
A trend must be explained both across a period on the periodic table (from left to right on the
row) and down a group on the periodic table (from top to bottom on a column)
We observed trends in:
•Atomic Radius
•Electronegativity
•Ionization Energy
•Reactivity
•Orbital Notation
Trend in Atomic
Radius
Atomic Radius increases as you move down
a group and decreases as you move (L-R)
across a period (in general)
Why? Coulombic Attraction!
Adding energy levels (electron shells) on to
the atom increases its size so as you move
down a group, each energy level increases
the radius of the atom.
When the energy level stays the same
(across a period) more protons are added
and attract the valence electrons closer to
the nucleus, this decreases the radius.
Trend in
Electronegativity
Electronegativity decrease as you move
down a group and increases as you move
(L-R) across a period (except Nobel Gases)
Why? Atomic Radius! Sort of!
Simplified version :
Increased atomic radius makes it harder for
the atom to attract electrons. As the radius
increases, the electronegativity decreases.
As the radius decreases, the
electronegativity increases because the
atom is more able to attract electrons.
Trend in
Ionization Energy
Ionization Energy decrease as you move down a
group and increases as you move (L-R) across a
period (except Nobel Gases)
Why? Atomic Radius! Sort of!
Simplified version :
Increased atomic radius makes it harder for the
atom to hang on to its electrons. As the radius
increases, the ionization energy decreases. As the
radius decreases, the ionization energy increases
because the atom is more able to hang on to its
electrons and it takes more energy to remove
them.
Trends in
Reactivity
For metals, we observed that reactivity increases as you
move down a group and decreases as you move (L-R) across
a period.
For nonmetals, we observed that reactivity decreases as you
move down a group and increases as you move (L-R) across
a period.
Why?
Metals want to donate their electrons, so their reactivity is
based on ionization energy. Lower ionization energy means
more reactive.
Non-Metals want to gain electrons, so their reactivity is
based on electronegativity. Higher electronegativity means
more reactive.
Orbital Notation
When writing electron configurations for neutral atoms,
the final orbital notation will align with the element’s
location on the periodic table.
Coefficient = period number for s & p OR
period minus 1 for d OR period minus 2 for f.
Letter = block of the table
Exponent = column in that block
Example: Gallium : 1s22s22p63s23p64s23d104p1
the final orbital notation is: 4p1
So Gallium will be found in the 4th period (row) in the
first column of p-block
Thursday November 17
After the Quiz
Get your goggles and a lab printout!
Read through the lab printout and have a separate
sheet of paper out for your observations and answers
to the questions.
Flame Test Lab
Just as a fingerprint is unique to each person, the color of light emitted by an element heated in a
flame is unique to each element.
When a substance is heated in a flame, the atoms absorb energy from the flame. This absorbed
energy allows the electrons to be promoted to excited energy levels. From these excited energy
levels, the electrons will eventually drop down to their original energy level.
When an electron drops from a higher energy level to a lower energy level, a particle of light called
a photon is emitted. The energy of the photon determines the color of the flame that you can
observe.
Because each element has a different spacing of electron energy levels (or shells), the possible color
of flames that can be emitted are unique to each substance.
Flame Test Lab
In this experiment you will observe the light signature of 6 different samples. Once you have observed
the samples you will use the data you collected to identify an unknown sample.
Possible Samples
Calcium Chloride
Copper (II) Chloride
Cobalt Chloride
Potassium Chloride
Barium Chloride
Strontium Chloride
CaCl2
CuCl2
CoCl2
KCl
BaCl2
SrCl2
Friday November 18
Learning Target: Periodic Trends – Claim, Evidence, Reasoning
Plan for today:
◦Claim, Evidence, Reasoning
◦Work on Study Guide!
Upcoming Dates:
Exam on Tuesday November 22nd
Study Guide Due Tuesday November 22nd
Claim. Evidence.
Reasoning.
Claim
A statement that you believe to be true.
“As you go down a group on the periodic table, the number of
valence electrons stays constant. As you go across a period on the
periodic table, the number of valence electrons increases.”
Evidence
Evidence: How do you know? A statement that supports your claim.
In the group 1A elements, Lithium, Sodium, Potassium, and
Rubidium all have one valence electron. In period 2, Lithium has 1
valence electron, Beryllium has 2, Aluminum has 3, Silicon has 4, and
Phosphorous has 5.
Reasoning
Reasoning: Explain your claim and evidence with scientific fact.
When you move across a period on the periodic table, the atomic
number increases by 1. This increases the proton number by 1, and
for the atom to be neutral, it also increase the electron number by 1.
Once you get to the end of the period where the noble gas is
located, the valence shell is full and another has to be added. In the
next period you restart with a new valence shell with 1 electron and
the pattern continues.
Tuesday November
nd
22
Exam Day! Hooray!
Please separate your chairs so that there are no more than 2 at
each table
Clear your table of everything except:
◦ Study Guide
◦ Something to write with
◦ Calculator