Which of the following subshells would be filled first when electrons are added to a gold atom?

Question

Quizplus · Accepted Answer

According to the Aufbau principle, electrons fill orbitals starting from the lowest energy level to the highest. For gold (Au), the 6s subshell is filled before the 5d subshell, which is in turn filled before the 6p and 6d subshells. The 4f subshell is filled even before the 5d, but since we're discussing the order for gold specifically, the 6s subshell is the first relevant one to be filled in this context.

Which of the Following Subshells Would Be Filled First When