Difference between revisions of "658: Orbitals"

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(Explanation: Put more emphasis on hunds rule, referenced the aufbau principle, and shortened the explanation of the pauli exclusion principle.)
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==Explanation==
 
==Explanation==
This comic is a pun on the {{w|Pauli exclusion principle}}, a principle that states (in part) that no two electrons in the same atom can ever be in the same quantum state simultaneously. The quantum state of two electrons is determined by four numbers, the first three determining its {{w|Atomic_orbital|orbital}} and the fourth its {{w|Spin_(physics)|spin}}, where spin can be one of two values, either +1/2 or -1/2. Thus there can only be two electrons in the same atom that share an orbital (and the two must have opposite spins), and such a pair of electrons is known as an ''orbital pair''.
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When determining where to place electrons in an atoms, three rules are generally used: the {{w|Pauli exclusion principle}}, the {{w|Aufbau principle}}, and {{w|Hund's rule}}. The Pauli exclusion principle, from which the pun is derived, states that no two electrons (or indeed any {{w|fermion}}) can occupy the same atomic state. Therefore, an electron orbital is limited to two electrons: one with a 1/2 spin, and the other with a -1/2 spin. The Aufbau principle states that lower energy orbitals are occupied previous to high energy orbitals. Hund's rule states that electrons will try to fill orbitals individually, and only pair up when every orbital has a lone electron in it.  
  
In this case, the people represent electrons, and rooms appear to represent orbitals, whether they be bedrooms or living rooms. "Romantic pair" is a play on "orbital pair". The "principle" at work here states that when engaging in romantic activity, only two people can be in a room at the same time, and thus any additional people are forced into different rooms. There is additionally a reference to the fact that as electrons are added to an atom, they will attempt to occupy the most stable or low-energy orbital, and so further electrons must occupy less stable/higher energy orbitals. Here, room comfort appears to equate to orbital energy, so the romantic partners all attempt to occupy the most restful or comfortable rooms, the bedrooms, leaving the lone roommate in a less comfortable location.
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In the comic, electrons are being equated to people, and rooms (or couches) are equated to orbitals. The reverse of Hund's rule is then followed: people will try to pair up in a room first, and only when all the couples have done so will rooms be allocated to single people. The Pauli exclusion principle here means that only two people can occupy a room at a time (should those people be romantically involved). The Aufbau principle therefore means that more restful rooms are filled previous to less restful rooms.  
  
 
The title text jokes about drunken party-goers, who ignore the Pauli principle perhaps out of inebriation. They then end up partying and sleeping together with many people in the living room, leaving the roommate stuck in the third desirable location, the hall lounge.
 
The title text jokes about drunken party-goers, who ignore the Pauli principle perhaps out of inebriation. They then end up partying and sleeping together with many people in the living room, leaving the roommate stuck in the third desirable location, the hall lounge.

Revision as of 17:56, 19 December 2016

Orbitals
Except the people filtering in late are the partiers, so you end up with drunken makeouts in the living room and the next roommate to return home has to sleep in the hall lounge orbital.
Title text: Except the people filtering in late are the partiers, so you end up with drunken makeouts in the living room and the next roommate to return home has to sleep in the hall lounge orbital.

Explanation

When determining where to place electrons in an atoms, three rules are generally used: the Pauli exclusion principle, the Aufbau principle, and Hund's rule. The Pauli exclusion principle, from which the pun is derived, states that no two electrons (or indeed any fermion) can occupy the same atomic state. Therefore, an electron orbital is limited to two electrons: one with a 1/2 spin, and the other with a -1/2 spin. The Aufbau principle states that lower energy orbitals are occupied previous to high energy orbitals. Hund's rule states that electrons will try to fill orbitals individually, and only pair up when every orbital has a lone electron in it.

In the comic, electrons are being equated to people, and rooms (or couches) are equated to orbitals. The reverse of Hund's rule is then followed: people will try to pair up in a room first, and only when all the couples have done so will rooms be allocated to single people. The Pauli exclusion principle here means that only two people can occupy a room at a time (should those people be romantically involved). The Aufbau principle therefore means that more restful rooms are filled previous to less restful rooms.

The title text jokes about drunken party-goers, who ignore the Pauli principle perhaps out of inebriation. They then end up partying and sleeping together with many people in the living room, leaving the roommate stuck in the third desirable location, the hall lounge.

Transcript

[Cueball is holding up a pointer in front of a diagram of a dorm apartment. On the diagram, there are two connected pairs of dots in each bedroom, and one dot on the couch.]
Cueball: Thus, once all the dorm bedrooms are occupied by romantic pairs, additional roommates are forced into less restful "living room couch" orbitals.
The Pauli Sexclusion Principle


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Discussion

The explanation implies that the romantic pairs must be male-female. I do not see this restriction in the comic. 108.162.219.223,

When I finally came to college, this comic was always on my mind. Then came a rather... er... covalent night. Except I didn't actually form the second pair, but came really close to doing such. But even then this comic always came to mind. International Space Station (talk) 08:59, 8 October 2015 (UTC)