[P-zac]

I'm stuck on this question:

Identify two nitrogen species that are unstable with respect to disproportionation, and identify the disproportionation products and write the balanced net reaction in each case. (The diagram given is here:
http://www.chem.ox.ac.uk/icl/dermot/nonmetals/lecture4/nonmetals445.gif )

** I'm thinking that N2 and HNO2 are the two unstable species since they are concave on the diagram but I'm unsure how the net reaction would look like.