We have investigated seven different reaction channels for each of the two symmetric charge-state reactants CO+N2 and N-2(+)+CO. For all the 14 reactions we have measured the integral cross sections as a function of relative energy and determined the corresponding reaction enthalpies. We make use of these values to find the heats of formation of NCO, NCO+, CNN, and CNN+. Similar branching ratios are observed for both charge-state reactions. This gives some hints that all reactions proceed through the same intermediate N2CO+.