Final answer:
The ground-state electron configuration for the Mn4+ ion is [Ar] 3d3, with three unpaired electrons, making it paramagnetic.
Step-by-step explanation:
The ground-state electron configuration for the Mn4+ ion can be determined by removing four electrons from the neutral Mn atom. Neutral manganese has an atomic number of 25, with the electron configuration [Ar] 3d54s2. Removing two electrons from the 4s orbital and then two from the 3d orbital (which is the higher energy orbital after 4s electrons are removed in ionization) results in the electron configuration of [Ar] 3d3, since the Mn4+ ion has lost four electrons in total. This configuration contains three unpaired electrons, indicating that Mn4+ is paramagnetic, as it will respond to the proximity of magnets due to the presence of these unpaired electrons.