Analysis of gas flow requires optical visualization techniques capable of detecting small refractive index variations. A Schlieren imaging system was constructed to observe these effects by converting inhomogeneities into visible brightness differences. The experimental Reynolds number of Helium was determined to be 1107 cm^3/s using this setup, denoting the transition between laminar and turbulet flow. In addition, gas flow was qualitatively analyzed for the cases of Oxygen, Carbon dioxide, Difluoroethane, and Tetrafluoroethane.