Question

Keeping the number of moles, volume and temperature the same, which of the following are the same for all ideal gases?
(a) Rms speed of a molecule
(b) Density
(c) Pressure
(d) Average magnitude of momentum.

Answer 1

Pressure of an ideal gas is given by PV = $\frac{1}{3}mn{u}^2$. We know that pressure depends on volume, number of molecules and root mean square velocity. Also, root mean square velocity depends on the temperature of the gas. Since the number of molecules, volume and temperature are constant, pressure of the gas will not change.

Thus, (c) is the correct answer.