Question

Use the periodic to fill in the numbers in the electron configurations shown below. Na: 1s22sC2pD3sE

Answer 1

Answer is: C is equal to 2, D is equal to 6 and E is equal to 1.

C, D and E represent number of electrons on each atomic orbital in sodium atom.

Electron configuration of sodium atom: ₁₁Na 1s² 2s² 2p⁶ 3s¹.

Atomic number of sodium is 11, it means that it has 11 protons and 11 electrons, so atom of sodium is neutral.  

Answer 2

Sodium's electron configuration is 1s2s3s1 or just [Ne] 3s1 for short. Hope I solved your problem but ask me for help if you need more!