The Arizona STEM Acceleration Project
Developing Understanding of Electron Configurations and
Relationship to Quantum Numbers
Developing Understanding of Electron Configuration and Relationship to Quantum numbers
A [9-12] grade STEM lesson (Chemistry)
Ty White
1/31/2023
Notes for teachers
This lesson works much better if students have already learned relationship between Bohr’s model and electromagnetic radiation. Connection especially to Line Emission Spectrum of Hydrogen and Balmer series, Paschen series and Lyman series so that students understand generation of EM radiation from electron behavior as well as the faults in Bohr’s model make the transition to QM easier to understand.
List of Materials
Standards
HS.P1U1.1 Develop and use models to explain the relationship of the structure of atoms to patterns and properties observed within the Periodic Table and describe how these models are revised with new evidence.
HS.P1U3.4 Obtain, evaluate, and communicate information about how the use of chemistry related technologies have had positive and negative ethical, social, economic, and/or political implications.
Standards
HS.P4U1.10 Construct an explanation about the relationships among the frequency, wavelength, and speed of waves traveling in various media, and their applications to modern technology.
HS+C.P1U1.2 Obtain, evaluate, and communicate the qualitative evidence supporting claims about how atoms absorb and emit energy in the form of electromagnetic radiation.
Objectives:
Today we will explain how an orbital can be used to represent both natures of an electron. Develop a metaphor that illustrates that idea.
Today we will describe electrons using different combinations of the 4 quantum numbers, from less informative to more informative information.
Today we will represent electron configurations graphically. We can describe an electron through the use of all four quantum numbers.
Agenda
Day 1 ~ After measuring wave and frequency properties of photons, relate them to electron behavior, and perform basic calculations.
Day 2 ~ Identify flaws in Bohr’s model between real world observations and Bohr’s explanations. Watch Dr. Quantum cartoon. Share and discuss picture of Solvay conference and consider cultural changes in Scientific Community.
Day 3 ~ Introduce Principle, Azimuthal and Magnetic location Quantum numbers. Discuss change from electron rings (orbits) to orbitals that represent both pockets of space as well as energy properties of electrons.
Let students drive connections/discovery for these activities:
Day 4 ~ Generate an “l” and “nl” table, make sure students connect how n and l values are connected.
Day 5 ~ Create periodic table riddle, challenging students to relate how periodic table structure represents quantum numbers (s, p, d, f blocks).
Day 6 ~ Apply riddle solution to full electron configurations
Day 7 ~ Introduce abbreviated electron configurations, relate to valence electrons and demonstrate group/family properties according to valence configurations.
Day 8 ~ Draw orbital notations, identify QN of individual electrons.
Use cartoon to introduce dual nature of electron.
Discuss limits of Bohr’s model treating electron as only a particle.
If further conversation, share Schrodinger’s cat, as well as the Quantum Time Eraser:
https://www.youtube.com/watch?v=p-MNSLsjjdo
Don’t be afraid to connect how double slit is reflected in sci-fi as “alternate realities/universes”. There is no confirmation, but let kids be excited and curious about interpretations!
Discovering Periodic Table layout/Electron configurations
Having introduced Principle QN, Azimuthal QN (and corresponding orbital shapes) and magnetic locations and number relationships, set kids with a challenge to explain why the periodic table looks “funny”, with boxes missing, mis-alignments, etc.
There will be struggle, and hyper-literalism regarding number connections/coincidence, but kids will discover the s2 p6 d10 f14 correlations.
Consider a reward/prize for first student to discover correlation. Color code blocks on table.
On the following day, encourage students to use nl chart and colored periodic table to determine how the electron configuration/energy levels of subsequent nl combinations are indicated.
Discovering Orbital Notations
Using orbital notations becomes a fun way for students to pictorially represent the energy levels they have practiced, and to identify an electron using all four of the QN they have learned.
Discussing electron spin can lead to exciting discussions about entangled particles.
Remind students that not only do electron and orbital notations strongly support measured periodic trends, but that this can lead to the ability to develop new technologies.
The fact that orbital structures represent both natures of an electron is the “magic” behind the technology of making quantum computing possible.
Assessment
Students are able to randomly select elements at random from the periodic table and demonstrate skill knowledge. Students can write full electron configuration, abbreviated electron configuration, and orbital notations, while identifying n, l, ml and ms values.
Differentiation
Students really love to explain this to their peers. This is an activity that makes students really proud of what they understand, and so starting remediation activities with peer tutoring is mostly effective.
Remediation
Extension/Enrichment
For enrichment, ask students to look up the current state of quantum computing, and quantum tunneling or quantum locking. They can then come back and share what they have learned and any exciting videos/examples with their peers.