Boltzmann Constant
The fundamental constant that converts thermodynamic temperature into microstate kinetic energy per particle.
Governing formula
k = R / Na = 1.380649 × 10⁻²³ J/K
SI unit
J/K
In depth
The Boltzmann constant bridges macroscopic thermodynamics and microscopic statistical mechanics. It enters Boltzmann's entropy formula (S = k ln Ω) and ideal gas particle energy (E_avg = ³/₂ k T).
Examples in the real world
Calculating average translational kinetic energy of air molecules at room temperature (300 K): E = ³/₂ k (300) ≈ 6.21 × 10⁻²¹ J.