Chemistry (Year 12)
Atomic Structure
What is the electron configuration of a sodium atom?
1s² 2s² 2p⁶ 3s¹
1s² 2s² 2p⁶ 3p¹
1s² 2s² 2p⁶ 3s²
1s² 2s² 2p⁶ 3d¹