ST. LOUIS -- When the Boston Red Sox signed Mike Napoli this past winter, there were a number of possible outcomes. He could hit a little, the way he had in 2012, putting up an OPS+ of 113. He could hit a lot, like he had in 2011, with a 173 OPS+ and 30 home runs. Most likely, he'd fall somewhere in between.
The fourth quantum number is the spin quantum number, s. There are only two values for s, +Â½ and -Â½. These are also referred to as 'spin up' and 'spin down'. This number is used to explain behavior of individual electrons as if they were spinning in a clockwise or counterclockwise.
As you know, a total of four quantum numbers are used to describe the positions and the spin of an electron in an atom. In your case, you must decide which possible values can be assigned to the fourth quantum number of an electron that resides in a 2s2 orbital. The principal quantum number describes the energy level, or shell, on which the electron resides. In this case, the electron is located on the second energy level, so n=2. The angular momentum quantum number, l, describes the subshell in which the electron is located. For an s-orbital, the angular momentum quantum number is equal to l=0. The magnetic quantum number, ml, tells you the specific orbital in which you can find the electron.