Ideal gas except for the specification of these constants. The results of the quantum Boltzmann gas are used in a number of cases including the Sackur–Tetrode equation for the entropy of an ideal gas and the Saha ionization equation for a weakly ionized plasma. The classical thermodynamic properties of an ideal gas can be described by two equations of state: The ideal gas law is the equation of state for an ideal gas, given by: where The ideal gas law is an extension of experimentally discovered gas laws. It can also be derived from microscopic considerations. Real fluids at low density and
Positive and negative parts Positive and negative parts In mathematics, the positive part of a real or extended real-valued function is defined by the formula Intuitively, the graph of formula_2 is obtained by taking the graph of formula_3, chopping off the part under the "x"-axis, and letting formula_2 take the value zero there. Similarly, the negative part of "f" is defined as Note that both "f" and "f" are non-negative functions. A peculiarity of terminology is that the 'negative part' is neither negative nor a part (like the imaginary part of a complex number is neither imaginary nor a part). The function "f" can