Answer :
Explanation :

B2+ is a Paramagnetic.  The filled orbitals are σ(1s)22, σ∗(1s)22, σ(2s)22, σ∗(2s)22. The half-filled orbitals are π(2pxx) and π(2pyy). Since it posses 2 unpaired electrons, it is Paramagnetic in nature.