Three biologically important diatomic species, either because they promote or inhibit life, are (a) CO,
(b) NO3 and
(c) CN-.
The first binds to hemoglobin, the second is a chemical messenger, and the third interrupts the respiratory electron transfer chain. Their biochemical action is a reflection of their orbital structure. Deduce their ground state electron configurations.

See Explanation

Explanation:

We can write the molecular orbital configuration of molecules in the same way as we write the orbital electron configuration of atoms. The valence electrons in the molecule are filled into molecular orbitals of appropriate energy in accordance to the Aufbau principle.

For CO;

σ2s2, σ*2s2, Π2py2, Π2pz2, σ2px2

For NO;

σ2s2, σ*2s2, Π2px2, Π2py2, σ2pz2, Π*2px1

For CN-;

σ2s2, σ*2s2, Π2px2, Π2py2, σ2pz2

These are the ground state electron configurations of these molecules.

it means there are 3 atoms of oxygen