Question

The orientation of an atomic orbital is governed by:
A. Azimuthal quantum number
B. Spin quantum number
C. Magnetic quantum number
D. Principal quantum number

Answer 1

‌Initially you must be aware of the term orientation and the terminology it is related with. You will know about the orientation then you can proceed with the question. Following this you should keep in mind what quantum numbers are and what is their role in orientation.

Complete step by step answer:
We know that, in chemistry orientation means the way of Collision of an orbital in a chemical reaction.
S orbital contains 1 orientation while P contains 3. D orbital contains 5 orientation while F contains 7. You can relate orientation in simple words to how an orbital is placed in the axis (this can be x axis, y axis, z axis and vice versa).
Quantum numbers can be described as the values of conserved quantities. Its four categories are designated different-different jobs.
Principal Quantum Number defines the state of the electron, Spin Quantum Number defines the angular momentum, Azimuthal Quantum Number describes the shape and orbital momentum of an electron, while Magnetic Quantum Number distinguishes the orbitals which are available within a subshell and defines the orientation of electron.
Magnetic Quantum Numbers divides the subshell into individual orbitals which holds the electrons. There are $2l + 1$ orbitals in each subshell.
.so the correct answer is option ‘C’.

Note: The magnetic quantum number distinguishes the orbitals available within a subshell, and is employed to calculate the azimuthal component of the orientation of the orbital in space. Electrons during a particular subshell (such as s, p, d, or f) are defined by values of ℓ (0, 1, 2, or 3).