Final answer:
The ground state electron configuration of a manganese atom (Z = 25) is [Ar] 4s² 3d⁵, obtained by following the order of increasing energy of sublevels as indicated by the building-up principle.
Step-by-step explanation:
To determine the electron configuration for the ground state of the manganese atom using the building-up principle (also known as the Aufbau principle), we start at the lowest energy level and progressively fill in electrons to higher energy subshells. Manganese has an atomic number of 25, meaning it has 25 electrons. Following the chart for the order of increasing energy of sublevels (like Figure 9.6.5 mentioned), we would fill the orbitals as follows:
Therefore, the electron configuration for the ground state of a manganese atom is [Ar] 4s² 3d⁵.