Which electron configuration corresponds to a neutral boron atom (atomic number 5) in the simplified orbital notation?

• A. $1s^{2}2s^{2}2p^3$
• B. $1s^{2}2s^{2}2p^2$
• C. $1s^{2}2s^{2}2p^1$
• D. $1s^{2}2s^{1}2p^2$

Answer: (C)

Verified step by step guidance

1. Identify the atomic number of boron, which is 5. This means a neutral boron atom has 5 electrons to place in orbitals.
2. Recall the order in which orbitals are filled according to the Aufbau principle: first fill the 1s orbital, then the 2s orbital, and then the 2p orbitals.
3. Fill the 1s orbital with 2 electrons, since it can hold a maximum of 2 electrons: \$1\,s^{2}$.
4. Next, fill the 2s orbital with 2 electrons, also fully occupied: \$2\,s^{2}$.
5. Finally, place the remaining 1 electron in the 2p orbital: \$2\,p^{1}\(. Combine these to write the full electron configuration as \)1\,s^{2} 2\,s^{2} 2\,p^{1}$.