Question

use the periodic table to answer the questions: which is the correct electron configuration for sodium (na)? 1s²2s²2p⁶2d¹ 1s²2s²2p⁶3s¹ 1s²2p⁶3d³

Explanation:

Step1: Determine sodium's atomic number

Sodium (Na) has an atomic number of 11.

Step2: Recall electron - filling rules

Electrons fill orbitals in the order 1s, 2s, 2p, 3s, 3p, etc. The s - orbital can hold 2 electrons, the p - orbital can hold 6 electrons.

Step3: Write the electron configuration

1s fills first with 2 electrons (1s²), then 2s fills with 2 electrons (2s²), then 2p fills with 6 electrons (2p⁶), and then the remaining 1 electron goes into the 3s orbital (3s¹). So the electron configuration of sodium is 1s²2s²2p⁶3s¹.

Answer:

1s²2s²2p⁶3s¹