Question #b2b26

1 Answer
Jan 6, 2016

d orbitals are more stable when they are half filled or fully filled.

Explanation:

The copper element has an atomic number of Z=29 which means that according to the Aufbau principle, the electron configuration should be:

29Cu:[Ar]4s23d9

However, it was found that copper's electron configuration as:

29Cu:[Ar]4s13d10

The explanation to this is that d orbitals are more stable when they are half filled or fully filled.

There is a similar example which is Chromium Cr where the electron configuration is:

24Cr:[Ar]4s13d5 instead of 24Cr:[Ar]4s23d4.