In this study the possibility of the simplification of plasma chemistry models was investigated in methane thermal plasma. Although, ionic species and electrons are important compounds of plasmas, their concentrations are much lower than of the neutral species. The role of non-neutral species, ions and electrons was investigated for a 1 v% methane-99 v% argon mixture by comparing the model concentration outputs obtained by thermodynamic and kinetic models and also by two thermodynamic models with and without ionic species. All the models gave identical results. This is an important conclusion for simulating plasma reactions as full ion containing mechanisms are not or hardly available. The product distribution on the initial methane concentration was also investigated and it turned out that the initial methane concentration has a major role in controlling the qualitative and quantitative distribution of the products.