Which of the following is the correct electron configuration for the element boron (B)?

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

Answer: (C)

Verified step by step guidance

1. Step 1: Identify the atomic number of boron (B), which is 5. This means boron has 5 electrons to place in its electron configuration.
2. Step 2: Recall the order in which electron orbitals are filled according to the Aufbau principle: electrons fill orbitals starting from the lowest energy level to higher ones, following the sequence 1s, 2s, 2p, etc.
3. Step 3: Begin filling the orbitals with electrons: first fill the 1s orbital with 2 electrons, then the 2s orbital with 2 electrons, and finally place the remaining electron in the 2p orbital.
4. Step 4: Write the electron configuration by indicating the number of electrons in each orbital: \$1s^2 2s^2 2p^1$.
5. Step 5: Verify that the total number of electrons adds up to 5 and that the configuration follows the Pauli exclusion principle and Hund's rule.