Question

1)Write the complete ground-state electron configuration for the silicon atom.
2)Use a noble gas core to write the electron configuration of phosphorus.

Answer 1

thats not physics, but chemistry, anyway I give it a try:

1:
\[Si = 1s² 2s² 2p ^{6} 3s² 3p²\]
2:
P = [Ne]3s²3p³