# Exercise 8 | Quantum Theory and Atomic Structure

Using the Aufbau principle, write the expected complete electron configurations for each of the following atoms by showing the electrons as half-headed arrows in partially filled orbitals.

S, Fe and C

S: 1s22s22p63s23p4

Fe: 1s22s22p63s23p64s23d6

C: 1s22s22p2