Kinetic Theory

Matter is made of atoms

Matter is made of atoms and molecules. Ancient Indian and Greek thinkers proposed atomic ideas, and modern science later established atomic theory. At

An ideal gas satisfies PV =

An ideal gas satisfies PV = μRT exactly, and also PV = k_B NT. Here μ is the number of moles, N is the number of molecules, R is the gas constant, and

Pressure arises from elastic collisions

Pressure arises from elastic collisions of molecules with container walls. Kinetic theory gives P = (1/3) n m v̄², where n is number density, m is mol

The average kinetic energy per molecule

The average kinetic energy per molecule is (1/2) m v̄² = (3/2) k_B T. Therefore, temperature is proportional to average kinetic energy and does not de

The rms speed is v_rms =

The rms speed is v_rms = sqrt(3k_B T / m). At the same temperature, lighter molecules have greater rms speed. For nitrogen at 300 K, the rms speed is