Use molecular orbital theory to determine whether f22+ is paramagnetic or diamagnetic.

We have to know whether F₂²⁺ is paramagnetic or diamagnetic.

F₂²⁺ is paramagnetic.

If number of unpaired electron in any species is equal to zero, the species is diamagnetic and the species contains unpaired electrons, then the species is paramagnetic.

The magnetic property can be explained using molecular orbital theory.

Total number of electron present in   F₂²⁺ is equal to 16 (i.e, 9+9-2). From the molecular orbital electronic configuration, number of electrons present in pi orbitals present is equal to 2.

So,  F₂²⁺ is paramagnetic.