Final answer:
The ground state electron configuration of cobalt is [Ar]4s²3d⁷, featuring a) partially filled 3d orbitals and unpaired electrons.
Step-by-step explanation:
The ground state electron configuration of the cobalt atom (Co, atomic number 27) is characterized by partially filled 3d orbitals with the presence of unpaired electrons.
In cobalt's electron configuration, the 3d subshell is not completely filled, which means that not all electrons are paired. Cobalt's ground state electron configuration is [Ar]4s²3d⁷.
Indicating that there are two electrons in the 4s orbital and seven electrons in the 3d orbitals, with some of these electrons being unpaired due to Hund's rule, which states that electrons will fill an empty orbital before they pair up.