Question

Number of angular nodes in 4d orbital is _____.
[A] 4
[B] 3
[C] 2
[D] 1

Answer 1

Hint: The nodal plane is a plane at which the probability of funding any electrons is zero. To find the solution to this question, identify the azimuthal quantum number of the given orbital. The number of nodal planes will be equal to the azimuthal quantum number ‘l’.

Complete step by step answer:
 To answer this question, firstly let us understand what an angular node is.
In a molecular orbital there are two types of nodes – angular node and radial node.
A radial node is the spherical surface where the probability of finding an electron is zero.
An angular node is also known as a nodal plane. A nodal plane is a region around the atomic nucleus where the probability of finding an electron is zero. A nodal plane is basically a plane that passes through the nucleus.
The number of angular nodes is equal to the azimuthal quantum number, l, and the number of radial nodes is equal to (n-l-1) where n is the principal quantum number.
Here, we have to find the number of nodes in a 4d orbital.
For that firstly let us find out the azimuthal quantum number that is l for the 4d-orbital.
Now, we know l for s-orbital is 0 and for p-orbital t s 1 and for d-orbital it is 2.
So, l i.e. the azimuthal quantum number is 2. It is equal to the number of angular nodes. So, the number of angular nodes is 2.
So, the correct answer is “Option C”.

Note: The number of radial nodes increases with increase in principal quantum number However, the number of nodal planes depends upon the shape of the orbital.
We know the shape of s-orbital is sphere i.e. there is just a sphere of electron density. Shape of the p-orbital is dumbbell shaped and that of the d-orbital is clover shaped, as if two dumbbell shapes are placed beside each other.
For s-orbitals, there are zero nodal planes. For p-orbitals we have one nodal plane and for d-orbitals, the number of nodal planes is 2.