Where does the value of n come from??

Question

im taking ap chem and im trying to understand the use of quantum numbers in electron configurations. i really really really don't understand where the value of n comes from....

Answer 1

I think the 'n' here tells you how many electrons there are in an orbital, or basically how large your orbital is. Moreover, it can also tell the distance/how far your electron is from the nucleus.

From your electron distribution mnemonics/electronic configuration, the value of 'n' is determined by the element's atomic number.

When n = 1... then we can see that it is very close to your nucleus... and so on. That's why there's no n = 0 because you can't define it where 0 is. Also, I think that the desciption on how large your orbital will be depends on the radius of your nucleus.

Answer 2

Can you type out the formula?  I took AP last year if I see it i'll remember

Answer 3

The quantum number n is the principal quantum number, and it tells us the major energy level in which an electron may be located.  The value of n corresponds to the energy levels in the Bohr model of the atom.

As we move from one atom to the next in the periodic table, each time we start a new period we increase the value n by 1.

The value of 2n^2 tells the number of electrons in the nth energy level.

For instance, the electron configuration of Zn is

1s2, 2s2 2p6, 3s2 3p6, 4s2, 3d10

The electron configuration shows the electrons in the various energy sublevels (s, p, and d) and the major energy levels where n has values of 1, 2, 3 and 4.  This tells us that there are four major energy levels being occupied by the electrons in zinc.