The given atoms in order of increasing number of unpaired electrons should be given by knowing their ground-state electron configurations.
An orbital is an area of space in which electrons are orderly filled. The maximum capacity in any type of orbital is two electrons. An atomic orbital is defined as the region of space in which the probability of finding the electrons is highest. It is subdivided into four orbitals such as orbitals which depend upon the number of electrons present in the nucleus of a particular atom.
There are three basic principles in which orbitals are filled by the electrons.
The electron configuration is the allocation of electrons of an atom in atomic orbitals. Electronic configuration of a particular atom is written by following the three basic principles. If all the atomic orbitals are filled by electrons, then the atom is diamagnetic in nature. Diamagnetic atoms are repelled by the magnetic field. If one or more unpaired electrons are present in an atom, then that atom is paramagnetic in nature. Paramagnetic atoms are attracted to the magnetic field.
To find: Direct the given atoms in order of increasing number of unpaired electrons by knowing their ground-state electron configurations