Textbook Question
Consider the molecule BF3. (a) What is the electron configuration of an isolated B atom? (b) What is the electron configuration of an isolated F atom?
10. Periodic Properties of the Elements
The Electron Configuration
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What is the complete ground-state electron configuration for silicon (Si)?
A
1s² 2s² 2p⁶ 3s² 3p⁴
B
1s² 2s² 2p⁶ 3s² 3p²
C
1s² 2s² 2p⁶ 3s² 3p⁶
D
1s² 2s² 2p⁶ 3s² 3p³
Verified step by step guidance1
Identify the atomic number of silicon (Si), which is 14. This tells us that a neutral silicon atom has 14 electrons.
Understand the order of filling electron orbitals using the Aufbau principle, which states that electrons fill orbitals starting from the lowest energy level to the highest. The order is: 1s, 2s, 2p, 3s, 3p, and so on.
Begin filling the orbitals with electrons: Start with the 1s orbital, which can hold 2 electrons, so we write 1s².
Continue filling: The 2s orbital can also hold 2 electrons, so we write 2s². Next, the 2p orbital can hold 6 electrons, so we write 2p⁶.
Proceed to the 3s orbital, which holds 2 electrons, so we write 3s². Finally, place the remaining 2 electrons in the 3p orbital, resulting in 3p². The complete electron configuration is 1s² 2s² 2p⁶ 3s² 3p².
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