Boltzmann constant(redirected from Boltzmanns constant)
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A constant occurring in practically all statistical formulas and having a numerical value of 1.3807 × 10-23 joule/K. It is represented by the letter k. If the temperature T is measured from absolute zero, the quantity kT has the dimensions of an energy and is usually called the thermal energy. At 300 K (room temperature) kT = 0.0259 electronvolt.
The value of the Boltzmann constant may be determined from the ideal gas law. For 1 mole of an ideal gas Eq. (1a)
Boltzmann constant(bohlts -măn, -mahn) Symbol: k . A constant given by the ratio of the molar gas constant to the Avogadro constant and equal to 1.380 658 × 10–23 joules per kelvin. It is the constant by which the mean kinetic energy of a gas particle can be related to its thermodynamic temperature.
one of the fundamental physical constants; equal to the ratio of the universal gas constant R to Avogadro’s number NA (the number of molecules in 1 mole of a substance): k = R/NA. It is named for L. Boltzmann. The Boltzmann constant enters into a number of the major relations of physics—the equation of the state of an ideal gas and the expression for the average energy of the thermal motion of particles (and thermal capacity itself). It also connects the entropy of a physical system with its thermodynamic probability.
The Boltzmann constant is k = (1.380622 ± 0.000059) x 10-23 joules per °K; this value corresponds to the most accurate data (as of 1969) on the constants R and NA. The value of the Boltzmann constant can be determined directly, for example, by the experimental verification of the laws of radiation. [3–1572–1; updated]