Multiple Choice
Which of the following correctly represents the orbital diagram for a neutral sulfur atom?
3
views
10. Periodic Properties of the Elements
The Electron Configuration
Struggling with General Chemistry?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Which of the following represents the correct electron configuration for a neutral atom of nickel (atomic number 28)?
A
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^6
B
1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10} 4s^2
C
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^8
D
1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^9
Verified step by step guidance1
Identify the atomic number of nickel, which is 28, meaning a neutral nickel atom has 28 electrons to place in orbitals.
Recall the order of orbital filling based on the Aufbau principle: electrons fill orbitals starting from the lowest energy level to higher ones, typically following the sequence 1s, 2s, 2p, 3s, 3p, 4s, then 3d.
Write the electron configuration by filling orbitals in order until all 28 electrons are accounted for: fill 1s (2 electrons), 2s (2 electrons), 2p (6 electrons), 3s (2 electrons), 3p (6 electrons), then 4s (2 electrons), and finally 3d orbitals with the remaining electrons.
Remember that the 4s orbital fills before the 3d orbital because it is lower in energy when empty, but once electrons start filling 3d, the energy levels can be close, so the 3d orbitals will hold the remaining electrons after 4s is filled.
Count the electrons in the 3d orbital after filling 4s with 2 electrons; since 28 - 18 (electrons in 1s through 3p) - 2 (in 4s) = 8, the 3d orbital will have 8 electrons, leading to the configuration $1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^8$.
Related Videos
Related Practice
The Electron Configuration practice set
Problem sets built by lead tutorsExpert video explanations