HemiChem: The Basics
The subatomic world of chemistry gets based upon a hemispherical model (HemiChem).

Electron subshells are longitudinal rings, in two hemispheres of OddCount sets a) at the same distance and b) at the same inclination angle. That makes those 2 x OddCount electrons all have the same potential energy and chemical behaviors.
This impacts every calculation for the Periodic Table (with sets as 2, 8, 8, 18, 18, 32, 32) based upon 2 x squares (2 hemispheres by the ring  π*rsquared).

Shell1 = 2 x 1squared = 2 x 1 = 2 electrons then full.

Shell2 and 3 = 2 x 2squared = 2 x 4 electron = 8 electrons.

Shell4 and 5 = 2 x 3squared = 2 x 9 electron = 18 electrons.

Shell6 and 7 = 2 x 4squared = 2 x 16 electrons = 32 electrons.
This allows all the advance physics understanding the quantum numbers, not as abstract, but isntead jsut as the hemispherical coordinates for those electrons in 3D with the overlay of the axis as one radial direction.

1st  Radial (r#). The count of layers/shells starting with 1.

2nd  Inclination (θ#) (I prefer this wording as subshells θ#=0 starts from the poles, s=2 at poles) / Longitude (that wording means counted from the equator which confuses students). These start from count=0 for 'at the poles.'

3rd  Latitude (preferred) / Azimuthal (from meridian, hard to teach) (φ#). These start from 0 as an arbitrary meridian, and build 2, 1, and +1, +2 around the 360/(2*MAX(θ#)1) angle in degrees.

4th  Hemispheres (z=X0=1/2 or +1/2). Which hemisphere for the longitudinal set.
Hopefully, you can see these longitudinal sets as oddcount sets with my notes as 2hemisphere cylinders (longitudinal ringsprings) overlaid on a current textbook graphic.
Electron configurations get better understood by replacing Lewis DotDiagrams with my Arno DotDiagrams.

In stable molecules, only complete, full longitudinalsubshellsets in each hemisphere are allowed. No partials.

This explains 3D engineering for the Elements in Columns that cause a) spectrum, b) electrical conductivity; and c) magnetism below. So, Copper becomes not a partial subshelld, but full endcapss which allows 'no shading' so lots of spectrum lines.
The goal is to go beyond formulas. Eventually, every chemistry challenge becomes 3D engineering that every level of student can understand.
Everything follows from the basics of the Atomic Model as hemispherical with electrons settling into subshells as longitudinal ringspring sets.
The Atomic Model: Questions and Answers
Answer 1
Answer 2
Periodic Table: Questions and Answers
Answer 1
Answer 2
Electron Configurations: Questions and Answers
Answer 1
Answer 2
Bonding: Questions and Answers
Hydrogen bonds:
Covalent bonds:
Ionic bonds:
Element Properites: Questions and Answers
Electrical conductivity / resistance:
Magnetism:
Spectrum:
States of Matter: Questions and Answers
Solid:
Liquid:
Gas:
Plasma:
BoseEinstein Condensate:
Chemical Reactions: Questions and Answers
Balancing Chemical Reaction Counts: