Video Transcript
What name is given to an atomic
orbital with the quantum numbers 𝑛 equals two, 𝑙 equals one, and 𝑚 sub 𝑙 equals
negative one?
Atomic orbitals are mathematical
expressions that describe the location of an electron around the nucleus of an
atom. Atomic orbitals come in different
shapes and sizes. We can refer to a specific orbital
using quantum numbers. The first is the principal quantum
number which is given the letter 𝑛. This quantum number tells us the
energy level the atomic orbital is in. 𝑛 equals two for the orbital in
this question. So we know the orbital is in the
second energy level.
The next quantum number is the
subsidiary quantum number given the letter 𝑙. This quantum number tells us the
orbital type or the subshell the orbital is located in. This spherically shaped orbital is
an s-type orbital, which makes up the s subshell. These three orbitals are p-type
orbitals, which make up the p subshell. For s-type orbitals, 𝑙 equals
zero. And for p-type orbitals, 𝑙 equals
one. 𝑙 equals one for the atomic
orbital in this question. So we know it’s a p orbital.
The final quantum number 𝑚 sub 𝑙
is the magnetic quantum number. This quantum number tells us the
orientation of the orbital. For these p orbitals, 𝑚 sub 𝑙
specifies which Cartesian coordinate axis the orbital is oriented along. However, to name an atomic orbital,
we don’t need to know the orientation. We only need to specify the energy
level and the orbital type using the number of the energy level and the letter of
the orbital. So the name of the atomic orbital
with the quantum numbers 𝑛 equals two, 𝑙 equals one, and 𝑚 sub 𝑙 equals negative
one is 2p.
