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Schrodinger mathematically showed that we have "cut up" the region outside the nucleus into smaller regions where the electrons are "located" (actually highest probability of finding the electrons) into 3 major subsections as follows.
Remember for Scrodinger these are the solution to Bohr equation (probability plots) spun in 3 dimensions to create the region:
*[Atomic orbital pictures after electron configuration]. Can click on this website to view actual pictures of orbitals and subenergy levels
- Energy Level (called Principle Quantum Number, n)
- Region that are the same distance from the nucleus.
- There are 7 of them called 1, 2, 3, 4, 5, 6, 7
- Subenergy Level (called Azimuthal Quantum Number, l )
- Region that have the same shape (probability plot)
- They are designated by letter: s, p, d, f, (from f on will use alphabet but never use them)
- Orbitals (called Magnetic Quantum Number, ml)
- The actual 3 dimension region of space outside nucleus where you will find the electron (of course is only the highest probability of finding the electron) with that given amount of energy.
- An example of an orbital is px. It has the shape of a p subenergy level and is "located" through the x axis. More details below.
With an understanding of the above subsection, another way of explaining what is going on is:
- If you sum all the orbitals together, you get the subenergy level region.
- Then if you sum all the subenergy level regions together, you get the Energy level region (remember, Bohr's energy level/7 concentric spheres).
- Then if you add all the energy level regions together, you get the region outside the nucleus where the electrons can be "located".
Is all the regions outside the nucleus accounted for when you sum all the orbitals, subenergy level and energy level?
- Answer: No, there are regions outside the nucleus where an electron in a given orbital can not be "located". These are called nodes.
- The number of nodes in an orbital of a given energy level = the number of the energy level.
- Example, for orbitals in the 2nd energy level, there are two nodes (do not need to know where they are).
Note: There is another way to explain the above information. Basically, all the orbitals are what physicist called "standing waves" (so all solutions to Scrodinger equation are also standing waves). So, you can explain orbitals, subenergy levels and energy levels and nodes with standing waves. I will not use this explanation here, though.
I know there are 7 energy level but what about:
Subenergy Levels? How do I know how many subenergy levels in a given energy level?
- Answer:The number of subenergy level in an energy level is equal to the number of the energy level.
- For example, in the 2nd energy level, there are two types of subenergy level, s and p
So a representation of a subenergy looks like: 2p
- where the 2 is the energy level and the p is the subenergy level
Orbtials? How many orbitals in a given subenergy level?
- Answer:The following table:
Subenergy Level vs # of Orbitals |
Subenergy Level |
# of orbitals |
s |
1 |
p |
3 (px, py, pz) |
d |
5 (d, d, d, d, d) see Note 1 |
f |
7 (f, f, f, f, f, f, f) see Note 2 |
- Note1: Actually the d orbitals have subscripts also but you are not going to be responsible for them. FYI, they are dxy, dyz, dxz, and the other two subscripts are too complicated to show in this format.
- Note2: Similarly for d orbitals, the f orbitals also have subscript that you will not be responsible for. Again, the subscripts are very complicated and can't show them using this format.
So a representation of an orbital looks likes: 2px
- where the 2 is the energy level and the p is the subenergy level and the subscript x shows the actual 3 dimension location of the orbital (shape does along the x axis)
- click on the webpage above to get the "pictures" of this orbital.
With subenergy levels and orbitals, there is a word commonly used, "degenerate". It means the region (orbitals and/or subenergy levels) are the same distance away from the nucleus. Which also means that electrons in these regions have the same energy as each other.
- For example, all orbitals of the same subenergy level are degenerate to each other (2px, 2py,2pz). Meaning they are same distance away from nucleus and the electrons in these orbitals have the same amount of energy.
In summary,
- Region we call subenergy level is the sum of all the orbital of that subenergy level
- Region we call energy levels is the sum of all the subenergy levels (including all the orbtials) of that energy level
- Region we call the Charged Cloud (region outside nucleus) is the sum of all the energy levels (that include all subenergy level that also contain all the orbtials).
- Finally, remember that the orbitals are actual 3-D regions outside the nucleus where the electron is "located" (highest probability of finding it) and the energy levels and subenergy levels are summation of orbtials.