Moderate

The correct order of orbitals is:

Correct answer: A. 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s

  • A. 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s
  • B. 1s, 2s, 2p, 3s, 3p, 3d, 4p, 4s, 5s
  • C. 1s, 2s, 2p, 3s, 3p, 3d, 3f, 4s, 5d
  • D. 1s, 2s, 2p, 3s, 3p, 4s, 4p, 4d, 5s

Explanation

The order of atomic orbitals is determined by their energy levels. This order follows the Aufbau principle and the (n+l) rule. Here's how it works:n represents the principal quantum number, which indicates the energy level (1, 2, 3, etc.).l represents the azimuthal quantum number, which describes the shape of the orbital (s=0, p=1, d=2, f=3).The (n+l) rule states that the orbital with the lower (n+l) value will have lower energy and will be filled first. If two orbitals have the same (n+l) value, the orbital with the lower n value will have lower energy.Option a follows the (n+l) rule correctly. For example, 4s (n+l = 4) has lower energy than 3d (n+l = 5).

Last updated

About Atomic Structure

Atomic structure covers the discovery of the proton, Planck's quantum theory, hydrogen emission spectra and the evidence for quantized energy levels. You will use quantum numbers to describe orbitals, distinguish s, p, d and f orbital shapes, and write electronic configurations, including the correct order of electron filling.

Practise Atomic Structure

922 free Atomic Structure MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.

Exams that ask Chemistry questions like this

Chemistry is on 12 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.

Related questions