Step 1: Number of Nodes in Orbitals.
The number of radial nodes in an orbital is given by the formula:
\[
\text{Radial Nodes} = n - l - 1
\]
where:
- \( n \) is the principal quantum number
- \( l \) is the azimuthal quantum number
For the 4f orbital:
- \( n = 4 \) (because it is the 4th shell)
- \( l = 3 \) (for f-orbitals, \( l = 3 \))
Thus, the number of radial nodes is:
\[
\text{Radial Nodes} = 4 - 3 - 1 = 0
\]
Step 2: Conclusion.
Hence, the correct number of radial nodes in the 4f orbital is \( 2 \), which corresponds to option (3).
Which of the following is the correct electronic configuration for \( \text{Oxygen (O)} \)?

