## 5 Conclusions  
Modeling combustion plasma for magnetohydrodynamic (MHD) power generation requires an ability to estimate the electric conductivity of plasma, which, in turn, needs a method to calculate the electron-neutral collision cross section for momentum transfer, taking into account the influence of temperature and the chemical composition of the plasma gas. Motivated by this need, the present study investigated the level of agreement or disagreement between four methods (based on four published studies in the literature) for predicting the electron-neutral collision cross section as a function of electron temperature alone for six relevant gaseous species and for a range of temperatures suitable for both air-fuel combustion and oxy-fuel combustion. This study showed that using an average electron energy in expressions designed for monoenergetic electron energy gives reasonable results that lie near those obtained using one or more other methods, with the exception of potassium vapor, as this method gives much larger values than any of the other three methods. Also, this study showed that using linear approximations for the collision cross sections seems to be acceptable in the temperature range of interest for combustion, with water vapor being a mild exception. Based on the performed analysis of the coefficients of variation, molecular hydrogen hasrelatively high consistency in its computed collision cross section, which slowly increases as the electron temperature increases. Carbon dioxide and water vapor (the major combustion products when completely burning a hydrocarbon fuel) become less scattering to electrons as the electron temperature increases, which is another reason (in addition to the intensified thermal ionization) to favor elevated-temperature oxy-fuel-based plasma over air-fuel-based plasma, since the former is associated with higher plasma electric conductivity and thus a better ability to generate electricity. This research received no external funding. Not applicable. Not dataset was used. The author declares that this research was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest. * [PERSON] et al. (1964) [PERSON]; [PERSON]; [PERSON] Determination of Momentum Transfer and Inelastic Collision Cross Sections for Electrons in Nitrogen Using Transport Coefficients. _Phys. Rev._**1964**, _135_, A1566-A1574. [CrossRef]
* [PERSON]. (1967) [PERSON]; [PERSON] Momentum-Transfer and Inelastic-Collision Cross Sections for Electrons in O\({}_{2}\), CO, and CO\({}_{2}\). _Phys. Rev._**1967**, _158_, 70-84. [CrossRef]
* [PERSON] and [PERSON] (1971) [PERSON]; [PERSON] Total Electron--Atom Collision Cross Sections at Low Energies--A Critical Review. _Rev. Mod. Phys._**1971**, _43_, 601-640. [CrossRef]
* [PERSON] (1974) [PERSON] Momentum-transfer cross sections for electron collisions with atoms and molecules. _At. Data Nucl. Data Tables_**1974**, _14_, 1-10. [CrossRef]
* [PERSON] (1995) [PERSON] Drift Velocity and Longitudinal Diffusion Coefficient of Electrons in CO\({}_{2}\)-Ar Mixtures and Electron Collision Cross Sections for CO\({}_{2}\) Molecules. _Aust. J. Phys._**1995**, _48_, 357-364. [CrossRef]
* [PERSON] (2002) [PERSON] Cross Sections for Electron Collisions with Carbon Dioxide. _J. Phys. Chem. Ref. Data_**2002**, _31_, 749-767. [CrossRef]
* [PERSON] (2004) [PERSON] Electron-atom collision cross sections in argon: An analysis and comments. _IEEE Trans. Dielectr. Electr. Insul._**2004**, _11_, 649-673. [CrossRef]
* [PERSON] and [PERSON] (2005) [PERSON]; [PERSON] Cross Sections for Electron Collisions with Water Molecules. _J. Phys. Chem. Ref. Data_**2005**, _34_, 1-22. [CrossRef]
* [PERSON] et al. (2022) [PERSON]; [PERSON]; [PERSON] Cross Sections for Electron Scattering from Atomic Tin. _Atoms_**2022**, _10_, 78. [CrossRef]
* [PERSON] et al. (1991) [PERSON]; [PERSON]; [PERSON] Plasmas in MHD power generation. _IEEE Trans. Plasma Sci._**1991**, _19_, 1180-1190. [CrossRef]
* [PERSON] et al.