# Which of the following is a #2p# orbital?

##
#A)#

#B)#

#C)#

#D)#

##### 1 Answer

The

#A# is an#ns# orbital, probably#3s# or#4s# , though it depends on their size.#B# is a#3d_(z^2)# orbital.#C# is a#3d_(xz)# orbital.

However, do not trust the image.

The

The

#n = 2# , for theprincipal quantum number.#n# can be one number in the set#{1,2,3, . . . }# .#l = 1# , for theangular momentum quantum numbersince#l = {0,1,2,3, . . . } harr {s,p,d, f, . . . }# .

If you recall:

- The total number of
**nodes**(radial or angular regions of zero electron density) is equal to#n - 1# . - The total number of
**angular nodes**(nodal planes or conic nodes) is#l# . - The total number of
**radial nodes**is#n - l - 1# .

Since

On either side of a *nodal plane* is a lobe of the *opposite* sign, and thus, there are two lobes on a

The

**orbital**, like so:

**Both** lobes on **same** sign, whereas it's the *ring* that is the *opposite* sign.

The