Question

The expression of average speed (u avg) of molecules of a gas is given by

• A. \(\sqrt{\frac{8RT}{\pi m}}\)
• B. \(\sqrt{\frac{8RT}{\pi M}}\)
• C. \(\sqrt{\frac{3RT}{\pi m}}\)
• D. \(\sqrt{\frac{3RT}{m}}\)

Hint:

The average speed depends on the temperature and molar mass of the gas. The higher the temperature or lower the molar mass, the faster the molecules move.

Answer 1

The Correct Option is B

The average speed of gas molecules can be derived from the kinetic theory of gases. The formula for the average speed of molecules is: \[ u_{\text{avg}} = \sqrt{\frac{8RT}{\pi M}}, \] where \( R \) is the universal gas constant, \( T \) is the temperature, and \( M \) is the molar mass of the gas.