### Quantum Numbers

Posted:

**Wed Oct 16, 2019 1:15 pm**Do the rules we learned about the different quantum values work for all atoms? Or just the ones with 1 e-? I know Lavelle mentioned it, but I am unsure where the "1 e-" fits in? Thanks!

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=20&t=47709

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Posted: **Wed Oct 16, 2019 1:15 pm**

Do the rules we learned about the different quantum values work for all atoms? Or just the ones with 1 e-? I know Lavelle mentioned it, but I am unsure where the "1 e-" fits in? Thanks!

Posted: **Wed Oct 16, 2019 1:17 pm**

The quantum numbers all describe a single electron in any atom. So it doesn't have to be an atom with ONLY one electron; Lavelle was just saying that the four numbers all describe a single electron – the energy, shape, orientation, and spin state.

Hope this helped!

Hope this helped!

Posted: **Wed Oct 16, 2019 1:21 pm**

To my understanding: Yes, the quantum numbers work for all atoms. The reason he used 1 e- to define the shells, subshells, etc is because a question relating to quantum numbers will most likely look something like:

"An electron has n=1, l=1, ml=0, ms=1/2. Find where that electron is located in terms of shells, subshells, etc."

Since each electron in an atom has a unique set of quantum numbers, only 1 e- will correspond with the above quantum numbers, so we have to find that specific e-.

Does this kind of answer your question? Basically the 1 e- comes into play because there's only 1e- in an atom that fits a specific set of quantum numbers (but the method in finding that sequence is the same for all atoms)

Hope this helped!

"An electron has n=1, l=1, ml=0, ms=1/2. Find where that electron is located in terms of shells, subshells, etc."

Since each electron in an atom has a unique set of quantum numbers, only 1 e- will correspond with the above quantum numbers, so we have to find that specific e-.

Does this kind of answer your question? Basically the 1 e- comes into play because there's only 1e- in an atom that fits a specific set of quantum numbers (but the method in finding that sequence is the same for all atoms)

Hope this helped!

Posted: **Wed Oct 16, 2019 2:14 pm**

I am still confused about how to calculate the magnetic quantum number (ml) based on the principal quantum number (n) and angular momentum number( l ). Could someone please explain to me the process of finding it? Like I know that (l) is dependent on (n) but the (ml) still confuses me.

For example, today in lecture Lavelle gave us two examples: n=2, l=1, ml=-1 AND n=3, l=2, ml=2.

For example, today in lecture Lavelle gave us two examples: n=2, l=1, ml=-1 AND n=3, l=2, ml=2.

Posted: **Wed Oct 16, 2019 2:23 pm**

Diana Chavez-Carrillo 3J wrote:I am still confused about how to calculate the magnetic quantum number (ml) based on the principal quantum number (n) and angular momentum number( l ). Could someone please explain to me the process of finding it? Like I know that (l) is dependent on (n) but the (ml) still confuses me.

m

The values of m

Each value of m

Posted: **Thu Oct 17, 2019 12:41 pm**

RoshniVarmaDis1K wrote:Diana Chavez-Carrillo 3J wrote:I am still confused about how to calculate the magnetic quantum number (ml) based on the principal quantum number (n) and angular momentum number( l ). Could someone please explain to me the process of finding it? Like I know that (l) is dependent on (n) but the (ml) still confuses me.

m_{l}is the magnetic quantum number that represents orientation. It labels the different orbitals of a subshell.

The values of m_{l}can range from -l to l. For example, if l=1 (which represents the p subshell), m_{l}can range from -1 to 1 (i.e. it can be -1, 0, 1). This makes sense because we know that the p subshell has 3 orbitals.

Each value of m_{l}represents an orbital. For example in this case, -1 could be the p_{x}orbital, 0 the p_{z}orbtial, and 1 the p[/sub]z[/sub] orbital.

Do you know if Lavelle will ask us on the exam to draw out the orbitals like px, pz, and py or would maybe just ask us to find what they are?

Posted: **Mon Oct 21, 2019 5:13 pm**

I think we definitely need to know how to describe an electron that is in a p orbital (i.e. be able to write/draw an electron configuration or write quantum numbers for a given electron.

If we need to draw p-orbitals, just remember that they are petal-shaped and that the three p-orbitals are always perpendicular to one another.

If we need to draw p-orbitals, just remember that they are petal-shaped and that the three p-orbitals are always perpendicular to one another.

Posted: **Tue Oct 22, 2019 11:29 am**

The 4 quantum numbers describe a specific electron in a specific atom/ion. For each electron in atom/ion, it has a different quantum number.