6.4 Quantum Numbers

[@warrensmith6377]

I've been watching these for DAT review and I like them. One thing with the aufbau principle that might make it easier for students to remember is just explaining what it means in German. I never really knew what the significance of the name was until I took German classes! Aufbau just means something like building up or construction, auf = up, bau = building. Everyone knows what those mean in English, and the "construction principle" is to start with the foundation, just like the orbitals. And similarly, you can't build a house and skip levels, just as the aufbau principle says with energy levels.

[@ChadsPrep]

Thanks Warren! I appreciate the feedback. I've been teaching this for 20 years and still continue to learn something new on a regular basis. And this is definitely something new. I was not aware of the German meaning behind the word. I plan to make an updated playlist next year and will definitely incorporate that into this lesson.👍 Happy Studying!

[@laurynvervaeke7910]

LIKE YOUR EX BOYFRIEND LMAOOOO that killed me

[@ChadsPrep]

Glad you enjoyed it, Lauryn!

[@johnstillman2935]

how is that everyone else confuses the hell out of things and you make it crystal clear

[@ChadsPrep]

Glad you think so!

[@sogazelle]

Awesome explanation...Thank you so much!!

[@shyamdevsahshyamdevsah5119]

Well thanks

[@remusion1310]

You teach very nice. 👍🏻

[@ChadsPrep]

Thank you Remus! 😃 Glad you found this lesson helpful!

[@Johnny-tw5pr]

Ah I wish the video was a bit longer so you could explain why the 4s subshell has less energy than the 3d

[@ChadsPrep]

the simple answer is that, when unfilled, the 4s is held closer to the nucelus than 3d (it dips down under it) due to the shape of the s orbital. Once filled, due to electron repulsion it spreads out so that a filled 4s is higher than energy than 3d.

[@Johnny-tw5pr]

@@ChadsPrep that's exactly what my book says too. I wrote that comment because I had an exam a few days later and I watched almost all your videos to revise since you cover the entirety of the high school chemistry syllabus in Greece. Thankfully this wasn't a question on the exam and I managed to get a grade of 100%. Thank you for the videos you make because honestly I probably wouldn't get a perfect grade without them.