enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Van 't Hoff equation - Wikipedia

    en.wikipedia.org/wiki/Van_'t_Hoff_equation

    The Van 't Hoff equation relates the change in the equilibrium constant, K eq, of a chemical reaction to the change in temperature, T, given the standard enthalpy change, Δ r H ⊖, for the process. The subscript r {\displaystyle r} means "reaction" and the superscript ⊖ {\displaystyle \ominus } means "standard".

  3. Boltzmann's entropy formula - Wikipedia

    en.wikipedia.org/wiki/Boltzmann's_entropy_formula

    where is the Boltzmann constant (also written as simply ) and equal to 1.380649 × 10 −23 J/K, and is the natural logarithm function (or log base e, as in the image above). In short, the Boltzmann formula shows the relationship between entropy and the number of ways the atoms or molecules of a certain kind of thermodynamic system can be arranged.

  4. Boltzmann constant - Wikipedia

    en.wikipedia.org/wiki/Boltzmann_constant

    The Boltzmann constant (k B or k) is the proportionality factor that relates the average relative thermal energy of particles in a gas with the thermodynamic temperature of the gas. [2] It occurs in the definitions of the kelvin (K) and the gas constant , in Planck's law of black-body radiation and Boltzmann's entropy formula , and is used in ...

  5. Table of thermodynamic equations - Wikipedia

    en.wikipedia.org/wiki/Table_of_thermodynamic...

    Quantity (common name/s) (Common) symbol/s Defining equation SI unit Dimension General heat/thermal capacity C = / J⋅K −1: ML 2 T −2 Θ −1: Heat capacity (isobaric)

  6. Third law of thermodynamics - Wikipedia

    en.wikipedia.org/wiki/Third_law_of_thermodynamics

    On the other hand, the molar specific heat at constant volume of a monatomic classical ideal gas, such as helium at room temperature, is given by C V = (3/2)R with R the molar ideal gas constant. But clearly a constant heat capacity does not satisfy Eq. . That is, a gas with a constant heat capacity all the way to absolute zero violates the ...

  7. Second law of thermodynamics - Wikipedia

    en.wikipedia.org/wiki/Second_law_of_thermodynamics

    The energy and entropy of unpolarized blackbody thermal radiation, is calculated using the spectral energy and entropy radiance expressions derived by Max Planck [63] using equilibrium statistical mechanics, = ⁡ (), = ((+) ⁡ (+) ⁡ ()) where c is the speed of light, k is the Boltzmann constant, h is the Planck constant, ν is frequency ...

  8. Entropy - Wikipedia

    en.wikipedia.org/wiki/Entropy

    For the expansion (or compression) of an ideal gas from an initial volume and pressure to a final volume and pressure at any constant temperature, the change in entropy is given by: = ⁡ = ⁡ Here is the amount of gas (in moles) and is the ideal gas constant. These equations also apply for expansion into a finite vacuum or a throttling ...

  9. Entropy (statistical thermodynamics) - Wikipedia

    en.wikipedia.org/wiki/Entropy_(statistical...

    The von Neumann entropy formula is an extension of the Gibbs entropy formula to the quantum mechanical case. It has been shown [ 1 ] that the Gibbs Entropy is equal to the classical "heat engine" entropy characterized by d S = δ Q T {\displaystyle dS={\frac {\delta Q}{T}}\!} , and the generalized Boltzmann distribution is a sufficient and ...