Which quantum number divides shells into orbitals?
- A. Principal
- B. Azimuthal
- C. Magnetic
- D. Spin
Correct Answer: Option B
The azimuthal quantum number, also called the angular momentum quantum number or the orbital quantum number, divides shells into orbitals. It is represented by the letter “l,” and it determines the shape of the electron orbitals inside an atom and the angular momentum of an electron.
Atoms have energy levels or “shells” that are made up of electrons. These energy levels or “shells” are identified by the principal quantum number “n.” Each shell is made up of smaller parts called “orbitals” that have their own shapes and places in space. This is done with the help of the azimuthal quantum number.
The integer values for the azimuthal quantum number ‘l’ range from 0 to (n-1) where ‘n’ is the principal quantum number. For example, if n = 2, then ‘l’ could be either 0 or 1. This makes two types of orbitals: the s-orbital, in which l = 0, and the p-orbital, in which l = 1. Each value of ‘l’ corresponds to a certain type of orbital, such as’s,’ ‘p,’ ‘d,’ ‘f,’ etc.
Different orbitals have different shapes. For example, s-orbitals are spherical, p-orbitals are dumbbell-shaped, d-orbitals have structures that look like clover leaves, and f-orbitals are even more complicated. The azimuthal quantum number also affects the number of ways an orbital can be set up in space. Each orbital can hold up to two electrons, so the azimuthal quantum number is a key factor in figuring out how the electrons are arranged in an atom and their chemical properties.