Difference between revisions of "Boltzmann constant"

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The Boltzmann Constant is the ratio of the [[Gas Constant R]] to Avogadro's number [[N<sub>A</sub>]].  It can be thought of as the gas constant for a single [[molecule]] (or even for an arbitrary particle in a [[colloidal solution]]) rather than for a [[mole]]<ref>Fundamentals of Physics, Fourth Edition by David Halliday, Robert Resnick, and Jearl Walker p582</ref>.
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The Boltzmann Constant is the ratio of the [[Gas Constant R]] to [[Avogadro's Number]] N<sub>A</sub>.  It can be thought of as the gas constant for a single [[molecule]] (or even for an arbitrary particle in a [[colloidal solution]]) rather than for a [[mole]]<ref>Fundamentals of Physics, Fourth Edition by David Halliday, Robert Resnick, and Jearl Walker p582</ref>.
  
 
The Boltzmann Constant is illustrated in the equation for the [[translational kinetic energy]] of a particle in thermal [[equilibrium]] with it's surroundings:
 
The Boltzmann Constant is illustrated in the equation for the [[translational kinetic energy]] of a particle in thermal [[equilibrium]] with it's surroundings:

Revision as of 15:05, 31 December 2007

The Boltzmann Constant is the ratio of the Gas Constant R to Avogadro's Number NA. It can be thought of as the gas constant for a single molecule (or even for an arbitrary particle in a colloidal solution) rather than for a mole[1].

The Boltzmann Constant is illustrated in the equation for the translational kinetic energy of a particle in thermal equilibrium with it's surroundings:

KEavg = 3/2 kT[2]

Where KEavg is the average Kinetic Energy of the particle, k is the Boltzmann Constant, and T is the Temperature in Kelvin.

According to NIST[3] the Boltzmann Constant has a value of 1.3806504 x 10-23 J/K with a standard uncertainty of 0.0000024 x 10-23 J/K and a relative uncertainty of 1.7 x 10-6 (this is represented by the concise form 1.380 6504(24) x 10-23 J/K

The Boltzmann Constant can also be represented in alternative units as 8.617385 x 10-5 eV/K

  1. Fundamentals of Physics, Fourth Edition by David Halliday, Robert Resnick, and Jearl Walker p582
  2. http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/kintem.html
  3. http://physics.nist.gov/cgi-bin/cuu/CCValue?k%7CShowFirst=Browse