This article discusses the viscosity of gases and molecular force, focusing on the kinetic theory of gases and its experimental validation. It explores how the coefficient of viscosity of gases is independent of pressure and proportional to the square root of absolute temperature. The article also examines the discrepancy between theoretical predictions and experimental results, attributing it to molecular force. It shows that molecular force significantly affects the viscosity of gases, particularly at lower temperatures. The article presents a mathematical model to account for molecular force in the calculation of viscosity, demonstrating that the coefficient of viscosity can be adjusted by considering the effect of molecular force. The study also compares theoretical predictions with experimental data for various gases, including air, hydrogen, and carbon dioxide, showing good agreement. The article concludes that the theory of viscosity, when accounting for molecular force, accurately explains experimental results and provides a foundation for understanding the behavior of gases under different conditions.This article discusses the viscosity of gases and molecular force, focusing on the kinetic theory of gases and its experimental validation. It explores how the coefficient of viscosity of gases is independent of pressure and proportional to the square root of absolute temperature. The article also examines the discrepancy between theoretical predictions and experimental results, attributing it to molecular force. It shows that molecular force significantly affects the viscosity of gases, particularly at lower temperatures. The article presents a mathematical model to account for molecular force in the calculation of viscosity, demonstrating that the coefficient of viscosity can be adjusted by considering the effect of molecular force. The study also compares theoretical predictions with experimental data for various gases, including air, hydrogen, and carbon dioxide, showing good agreement. The article concludes that the theory of viscosity, when accounting for molecular force, accurately explains experimental results and provides a foundation for understanding the behavior of gases under different conditions.