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Q3: Week 2  – 2/7 – 2/11

                                                                                                                                                                                 Jump to:  Tuesday,   Wednesday,  Thursday,  Friday                                                                                                                  ______________________________________________________________

2/7 – Monday – B Day – 2, 3b/4 Lab       

Main focus –                                                                                                                                                         
                                                  

    a) To discuss the Bohr model of the atom and its combination of classical physics and              the new quantum theory.

    b) To observe emission spectroscopy and make calculations with the Balmer                               Equation.

 

Period 2:  – Bohr, Balmer equation, inverse square law – demo, quantum leaps

1.  Complete the light theories, positive and negative.

2.  Introduce the Bohr Model, plane, Balmer equation, inverse square – law

3.  Bright line Spectrum Demo.

Period 3/4:  – Bohr, Balmer equation, inverse square law – demo, quantum leaps

1.  Complete the light theories, positive and negative.

2.  Introduce the Bohr Model, plane, Balmer equation, inverse square – law

3.  Bright line Spectrum Demo /absorption theories.

 
Plank = Energy was quantized by a multiple of (h) = Plank’s constant
 
Einstein = Light was quantized into packets called photons and each electron interacted with a single photon
 
These light ideas was on a crash course towards the particle model of the atom and Neil’s Bohr was the first to develop a model of the atom to that was quantized in terms of the electrons.  He was able to expand Rutherfords particle model with electrons that were organized in shells that had definite energy levels based on the proximity to the nucleus.  These electrons emitted or absorbed photons of electromagnetic energy based on electrons transitions to and from these energy levels. 
 
Neils Bohr was able to develop a quantized model of the atom by using another phenomenom which were the Bright Light Emissions Spectra, known for over 50 years.
 
Bright Line Spectra was another phenomenon that know one knew how to explain and yet since the 1850’s it was used to identify elements based on the type of light emitted by elements when they are subject to high energy.

These Bright Lines, Photons of a specific Energy ( E = hv) are emitted from each element differently and thus can be used to identify elements.  Helium, He was discovered from the light given off from the sun.  Light from the sun was diffracted and all of the bright lines were identified from all known elements at the time and the Bright Lines that remained was thought to have come from a new element that was yet to be discovered on earth.  They called it Helium, the Greek God of the Sun (Helios). Thirty years later Helium was discovered on Earth and it had the same spectral lines as the mysterious new element discovered on the Sun!
 
I will perform this demo today and tomorrow and we will look at the spectral lines of a few elements and some molecules.
 
Neill’s Bohr was the first to explain this phenomenon by creating a model of the atom that suggested that the energy levels in an atom are quantized and that the spectral lines are due to electrons making quantum leaps from higher to lower energy levels. 
  Bohr took Plank’s and Einstein’s ideas as was the first to make a quantum model of the atom that stated that electrons can only have discreet energy levels (quanta) and that when they move (quantum leap) the energy changes result in photons of light being released (when moving back to the ground state) or absorbed (when moving to higher energy states).  Before Bohr the model of the atom was Rutherfords, where electrons orbited the nucleus but could have any energy

Electron Emissions!

Light into the Bohr Model:

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2/7 – Monday Homework: –                                                                                                                                                                                                                           

1:   Please watch the lecture below (AP Lecture Balmer Equations) and follow me through the backside of the  Atomic structure 2 – bohrs.pdf worksheet.
 
THE last question should read:
 Calculate the Energy needed for an electron to transition from the 4th energy shell to the 2nd energy shell?  What color of light is this. 
 
2.  Complete questions 1 and 2 in atomic structure 3 worksheet and review with the key. 
     
Atomic structure 2 – bohrs.pdf

View Download

 
atomic structure 2 – Bohr Key p.pdf

View Download

 
atomic structure 3 – de Broglie Key.pdf
 
Atomic structure 3 – de Broglie.pdf

View Download

 

3.  Complete the Form Below after or with the Photoelectric Effect Simulation lecture below . 
 
                                                                                                                                                     

1: AP Lecture Balmer equations:

Photoelectric effect Explained – Phet demo 

 
2 : Photoelectric Effect 21-22 Form:  

End of Wednesday!

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2/8 – Tuesday – A Day – 2/3a Lab, 4   

Main focus –                                                                                                                                                         
                                                  

    a) To identify elements by their Bright Line spectrum.

    b) To Compare and contrast Absorption and Emission Spectrum

    c) To review the Limitations of the Bohr Model

 Period 2/3: Review/Positive and Negative theories of light 

1.  sunset demo – light is made of different photons with varying energy (frequencies).

2.  To complete the Bright Line Spectrum demo with gas discharge tubes.

3.   Absorption Spectrum demo – Absorption Spectroscopy = Negative Theory

   Positive theory – Newtons wheel/ light stick wheel/ sunset demo / phosphorescence demo /

4.   LIMITATIONS of the Bohr model.                                                                                                                                  

Period 4: Review/Positive and Negative theories of light 

1.  Absorption Spectrum demo.
Positive theory – Newtons wheel/ light stick wheel/ sunset demo / phosphorescence demo /

2.  QUANTIZED DEMO LIMITATIONS of the Bohr model.   
3. LIMITATIONS of the Bohr model.  

                                                     

Yesterday I started today talking the bright line spectrum that Bohr interpreted from the Balmer equations. He was able to show the the “bright lines” of Hydrogen were the photons of light emitted by electrons returning to their most stable state (closer to the nucleus or mom). 
 
These Bright lines were made by pure elements being “excited with energy” (electrons moving away from atom in higher energy shells) in gas discharge tubes and when these excited electrons move back to their stable low energy positions photons of light are emitted that are specific to electron moving or transitioning from a higher energy shell to a lower energy shell.
 
Bright line spectrums were know since 1850’s and were specific for each different element.  This means that each different element had its own unique spectrum could be used to identify elements. It was a spectral fingerprint.  The Bright line spectrum was used to discover Helium from light of the sun 30 years before it was discovered on Earth.

 

Niels Bohr accomplishment was to describe the known Bright Line Spectrum of Hydrogen in terms of emissions of photons of light of specific energy related to electrons returning from an excited state (from a constant supply of energy).  The red line in the Bright line spectrum below is due to electrons “leaping” from the 3rd energy shell to the second!

                           

 

 

Absorption spectra demo:

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2/8 – Tuesday Homework: –                                                                                                                                                                                                                           

1. Please complete the Bright Line spectrum worksheet. 
 
Bright line spectra – .pdf

View Download

 
Bright Line spectrum Key p.pdf

View Download

 
2. Clash of Titans Timeline continues.  Please continue with your timeline from 27:00 – 34:55.
Clash of the Titans
http://topdocumentaryfilms.com/atom-tim/   or https://www.youtube.com/watch?v=Y-AiqCp7Vlc
 
 

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2/9 – Wednesday – B Day – 2, 3b/4 Lab

Main focus –                                                                                                                                                         
                                                  

    a) To complete atomic structure experiments that lead to the Mass Spectrometer

   

Period 2:  

1. limitations to Bohr’ s model 

2. Louis De broglia –   wave behavior of matter!!!!

 

3.  Experiments that support De boglia —-> Quantum mechanical model is developed
 
Period 3/4:  

1. limitations to Bohr’ s model 

2. Louis De broglia –   wave behavior of matter!!!!
 
3.  Experiments that support De boglia —-> Quantum mechanical model is developed 
 
OUR New Equation today! 
 
This was a formula that from a PhD student that needed Einsteins approval.  It used Einstein’s formulas to form a new formula that proposed all things that have matter also have wavelengths! Or better yet, all things that have matter also have wave behavior!  This was the first proposed idea of wave /matter duality that was needed for Quantum Mechanics.  Einstein loved the work because it allowed the conservatives to view the atom exclusive of the mathematics of the Copenhagen interpretation of quantum mechanics (Niel’s Bohr’s group).                                                                                 

 

Light into the Bohr Model and beyond!

Bohr into De broglie Lecture: (today’s lecture)

 

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2/9 – Wednesday Homework: – 

 
1. Please complete the de Broglie worksheet and review with the key. 

     You should only have questions 3 and 4 left!           

 
atomic structure 3 – de Broglie Key.pdf
 
Atomic structure 3 – de Broglie.pdf

View Download  

2. Complete the Timeline of the Clash of the Titans – due Friday – hardcopy or digital.  

3. Complete the Form below. You will need the watch the to the end of the Clash of the Titans to complete. You will have one submission tonight  and another tomorrow night after I completely review these concepts and scientists in class.

 
3 : Bohr to DeBroglie Atomic Structure Form:
*Please use 1 m/sec for the velocity of the proton in question 8 of the form.

End of Wednesday!

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2/10 – Thursday – A Day – 2/3a Lab, 4 

Main focus –                                                                                                                                                         
                                                  

    a) To discuss the quantum mechanical models developed 

    b) To use the solutions of the Shrodinger equation to describe the atom and electron               arrangements.

Period 2/3:  – 

1.  Bohr limitations – His model was doomed…..(wave behavior of electrons!)
2.  Louis DeBroglia – Electrons as waves! – Matter has waves properties!!!
 3. De Broglie wavelength ,Compton effect, Davidson  – Germer, William Thompson
 
4. Shrodinger’s equation —> quantum numbers
 
The math from the Bohr team – Copenhagen interpretation gave some very hard phenomenon to think about that must be accepted:
 
            1) Heisenberg Uncertainty principle
            2) Superposition
            3) Quantum Entanglement
            4) Multiple Worlds Theory – explains the collapse of the superposition (wave function)
 
In the words of Richard Feynman, (Nobel Prize winner, 1965 – quantum electrodynamics)
 
“If you do not like it. Too bad! Go somewhere else! That is how the universe works!” 
 
Quantum Numbers – worksheet 1.pdf
View Download
 
Atomic Structure 4b -Electron configuration.pdf

  

 Period 4:  – 

 Same as above. 

  

                                                                                                         

Last Slides for Quantum Mechanics!

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2/10 – Thursday Homework: – 

 

1.  Make another submission to last nights Form if you need to. I have graded the form and I have sent out the grades.  It is not on auto- reply.

 
2.  Watch the quantum number lesson video and complete the form. This reviews the solutions to the Schrodinger equation that will allow us to determine the energy and relative positions of the electrons around the nucleus based on their quantum energy states.  All this means is that we will get electron configurations from the equation FROM the solutions to the Schrodinger equation.
 
Make sure you have completed your timeline before you begin this lecture.  This lecture about the values that we get from the Schrodinger equation that was “discovered over a weekend” that helped team Einstein (who was pitted against Team Bohr) have more of a visual model of the atom using standing waves of electrons in orbitals).  Remember that Team Bohr described the atom and its behavior entirely with mathematics and equations.  It is the solutions (quantum numbers) to the Schrodinger equation that have lead us to our current electron configuration of atoms that explains all of the chemical nature of atoms.
 
Remember electron configurations this summer?   Na:  1s22s22p63s1
 
This is the arrangement of electrons in an atom based on electrons existing in standing waves in a region called an orbitals. These orbitals are quantized and their arrangement is also based on its proximity to the nucleus, much like Bohr’s first quantum model of the atoms with electrons moving in orbits.  Example:  3s electrons are farther away from the nucleus and have greater energy (unstable) than 1s electrons who are closer to the nucleus (more stable).  The difference to the Bohr model is that electrons are existing as standing waves in a particular geometry.  The basics of the Bohr model is still upheld (that is why he won a Nobel Prize for his first model). 

                                                                                                                                                                                                                                You learned electron configurations this summer and did so without the rest of the atomic structure history and concepts.  We will re-vist electron configurations but will develop the concepts through quantum numbers! 

Quantum number lecture:

 
2 : The Quantum number Form:

End of THursday!

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2/11 – Friday – B Day – 2, 3b/4 Lab

Main focus –                                                                                                                                                         
                                                  

    a) To use the solutions to the Schrodinger Equation to write electron configurations.

    b) To define the quantum numbers to standing waves of orbitals (wave potentials).

     c) To build an orbital diagrams.

 

Period 2/3/4:  – 

1.  Review the quantum number form.

Quantum Number form 1920 Key p.pdf
View Download

 

2.  Complete the Quantum numbers worksheet with the class to cements the concepts of quantum numbers that are solutions to the Shroedinger’s Equations.

Quantum Numbers – worksheet 1.pdf
View Download

Quantum Numbers – worksheet 2.pdf
View Download

Atomic Structure 4b -Electron configuration.pdf

 

3.  Wrote the configuration of the Uranium to demonstrate how the periodic table is a guide to the electron configurations (especially the overlapping of energy levels).

Need to show students the shapes of orbitals and where the g begins!!

TODAY’s NOTES:

Electrons are arranged from lowest energy to higher energy = Aufbau Principle
 So they fill from lower n to higher n  and from lower energy orbitals (l) to higher energy orbitals. Electrons fill sublevels in order ( s,p,d,f).
 
Electron are arranged in        n = principle energy levels
                                                    l  = sublevels
                                                 ms =  individual orbitals (actual 3 -d shape where pairs of electrons can exist)
 
Every Electron has a unique set of 4 quantum numbers (including spin ms) = Pauli Exclusion Principle
These quantum numbers describe how the electrons are arranged in the atom based on energy.
 
                                      The basic organization is principle energy level (n = 1, 2, 3, etc.) – “shell”
 
                                                                                     sublevel  (s,  p,  d,  f, ) – type of orbital and all of its orientations
                                                                                                   l = 0,  1,   2,  3
 
                                                                                      orbital (individual orbital of a single orientation of a sublevel)
                                                                                                        ml = -l , 0, +l
 
This arrangement uses notation that describes the organization of the electrons in principle energy levels and sublevels. The exponent is the number of electrons in the TOTAL sublevel that includes all the orbitals of different orientation of the same sublevel.
 
s = 1 orbital   (l = 0, ml = 0)
p = 2 orbitals (l = 1, ml = -1,  0, +1)
d = 5 orbitals (l = 2, ml = -2, -1, 0, +1, +2)
f  = 7 orbitals (l  = 3, ml = -3, -2, -1, 0, +1, +2, +3)
g =  ?
 
Electron configuration of Al:           Nucleus:  1s22s22p63s23p1
 
Orbital notation for Al:
Each box represents a single orbital.
 
Which electrons are the most stable? Unstable?
 
*Connections – Our quantum numbers refer to specific energy levels allowable by each quantized element.  The arrangement of electrons in quantized energy orbitals that were solutions to the Erwin Schrodinger equation (quantum numbers) are actually hidden in the periodic table that was already arranged according these energy levels (unbeknownst to Mendeleev and Moseley!!) The periodic table that we use is a condensed version that does not insert the  f block ( l = 3) because it would not fit on most pages!!!!
 

 

 

Light into the Bohr Model:

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2/11 – Weekend Homework: – 

1.  Please complete the Quantum Numbers – worksheet 1.pdf if you did not do so in class and review with the key below:

 

Quantum Numbers – worksheet 1.pdf
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Quantum Numbers – worksheet 1 Key.pdf
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2.  Please view the lecture of me reviewing the first 4 elements in the Quantum Numbers – worksheet 2.pdf and then complete the worksheet. Review with the key below.

Quantum Numbers – worksheet 2.pdf
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Quantum Numbers – worksheet 2 Key.pdf
 
 3. Period 4 Class only:  Please write all the configuration from the worksheet below and review with key or with the 2 lectures posted at the bottom of this page if you need help.  Period 2 class do not complete this yet!!!
 
Atomic Structure 4b -Electron configuration.pdf
 
Atomic Structure 4b -Electron configuration key.pdf
View Download

 

 

Review of quantum number worksheet 2 (the 4 atoms) :

 

 electron configuration 1   electron configuration 2