The electron configuration for chromium is 1 s 2 2 s 2 2 p 6 3 s 2 3 p 6 3 d 5 4 s 1 instead of 1 s 2 2 s 2 2 p 6 3 s 2 3 p 6 3 d 4 4 s 1 . The configuration is an exception to the _____.
A Heisenberg uncertainty principle
B aufbau principle
C Schrödinger equation
D Pauli exclusion principle
