Electrons in an atom behave very differently. Students will see that when an electron becomes a part of an atom, it is spread around the nucleus like a cloud. They will also study the shapes of s- and p-orbitals. Later, students will cover the Pauli Exclusion Principle, which states that only two electrons can share the same orbital.
This lesson is a part of MEL Chemistry VR. Learn more →
atoms, electrons, electron cloud, electron orbitals, orbital shape
From the Bohr-Rutherford diagram:
- Electrons actively revolve around the nucleus
- Electrons are roughly the same size as protons and neutrons
- The 'distances' from the nucleus to the electrons and between electrons
- Learn that the nucleus is surrounded by an electron clouds
- Begin exploring orbitals
- Learn that two electrons can share one orbital
- Learn that orbitals have different shapes and sizes
History and sources of knowledge
- History from Rutherford to Bohr and modern theory.
- Quantum theory: description, computational models.
- Scientific approach: the best scientific explanation is based on evidence (observations) and scientific knowledge. A theory should explain observations and make predictions.
Topics to discuss
- How and why did atomic models develop? The scientific approach mandates correcting a hypothesis if it is insufficient to explain new findings (observations, measurements).
- How can we trust theories about things we can't see?
- Emissions and the absorption spectra of elements as a source of information about energy levels.
- Energy level concepts.
- Ladder with a fixed position analogy: when climbing a ladder, you can only step on the rungs' fixed positions, not in between them. Likewise, electrons can only have certain energy levels. In this analogy, the gaps between the ladder's rungs would be much smaller, and smaller still at the top.
- Quantum theory.
- What’s the difference in shape between s- and p- orbitals? (symmetry description)?
- How many electrons do the first 3 noble gases have (with explanation)?
Please see below for the link to a Google form containing a quiz on the material above.
This can be assigned during class time or as homework. The quizzes are marked and the system shows which questions students get correct and incorrect. Please note that students should record their scores, as they will not be viewable later.