Multiple Choice
The sulfur atom has 16 electrons. What is the correct electron configuration for sulfur?
4
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 is the correct electron configuration for strontium (Sr, atomic number 38)?
A
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^1
B
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2
C
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 4d^{10}
D
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5p^2
Verified step by step guidance1
Identify the atomic number of strontium (Sr), which is 38. This means Sr has 38 electrons to be placed in orbitals according to the Aufbau principle.
Recall the order of orbital filling based on increasing energy levels: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, etc.
Fill the orbitals with electrons following the order and the maximum number of electrons each orbital can hold: s (2 electrons), p (6 electrons), d (10 electrons).
Write the electron configuration by adding electrons in each orbital until you reach 38 electrons, ensuring the 5s orbital is filled before starting to fill the 4d orbital.
Compare the given options with the correct electron configuration you derived, which should end with 5s^2 (not 5s^1 or 4d^{10} or 5p^2) because strontium's valence electrons fill the 5s orbital.
Related Videos
Related Practice
The Electron Configuration practice set
Problem sets built by lead tutorsExpert video explanations