Question

How many orbitals are present in a D subshell?

Answer 1

An electron shell is basically an orbit in which electrons revolve around an atomic center called nucleus. Now In atomic chemistry shells are made up of subshells, subshells are made up of orbitals which in turn consist of electrons in them. In order to find the number of orbitals in a particular subshell we will firstly find the maximum number of electrons which can be present in that shell and then divide it by the maximum number of electrons in an orbital.

Complete answer:
Maximum number of electrons present in a subshell is given by the formula $4l\,+\,2$, where $l$is the azimuthal quantum number.
For D subshell, we know that the value of $l$is $2$
Hence maximum number of electrons present in D subshell is= 4(l) +2
Hence maximum $10$ electrons are present in the D subshell.
Now we know the fact that the maximum number of electrons present in an orbital is $2$. It means no individual orbital can have electrons more than $2$
Total number of orbitals can be calculated by the formula shown below;
No. of orbitals = $\dfrac{Total\,number\,of\,electrons\,in\,a\,subshell}{2}$
For D subshell
No. of orbitals = $\dfrac{10}{2}\,=\,5\,orbitals$
Therefore, total five $(5)$orbitals are present in the D subshell.

Note: Alternatively, one can cross check the answer with the help of a short formula as depicted below;
Number of orbitals in a subshell = $2l\,+\,1$. For D subshell we know $l=2$
Hence the number of orbitals in D subshell by this formula will also be $2(2)\,+1\,=\,5\,orbitals.$ It's important to learn the values of $l$for different subshells. Always use such type of Short formulae in MCQ type of questions.