Question

Which of the following is not the correct order regarding the energy of orbitals?

• A. \(2p<3s\)
• B. \(3p<4s\)
• C. \(3d<4p\)
• D. \(4d<5s\)

Hint:

Always consider electron configurations and energy levels when comparing orbital energies, as common exceptions often occur.

Answer 1

The Correct Option is D

Step 1: Recall the energy ordering of atomic orbitals. Typically, the energy of orbitals increases with the principal quantum number \(n\), but due to the penetration and shielding effects, some orbitals like \(4s\) are lower in energy than \(3d\). 
Step 2: Identify the incorrect order. The correct energy order should be \(4d>5s\), making option (4) incorrect because it states \(4d<5s\).