In the present study, we found that the EA leading to C2H2 -(reaction 25) required an energy of 0.8 eV (79.4 kJ/mol), which makes it highly probable in our plasma discharge. Also, note that C2H2 -can be obtained already in the dissociation of C5H5 -(reaction 19). The C2H2 -ion can then proceed to decompose, forming C2H, CH2, CH, C2, C, H2 and H, according to reactions 26-28.