Search results
Results from the WOW.Com Content Network
The gas constant occurs in the ideal gas law: = = where P is the absolute pressure, V is the volume of gas, n is the amount of substance, m is the mass, and T is the thermodynamic temperature. R specific is the mass-specific gas constant. The gas constant is expressed in the same unit as molar heat.
Isotherms of an ideal gas for different temperatures. The curved lines are rectangular hyperbolae of the form y = a/x. They represent the relationship between pressure (on the vertical axis) and volume (on the horizontal axis) for an ideal gas at different temperatures: lines that are farther away from the origin (that is, lines that are nearer to the top right-hand corner of the diagram ...
The ideal gas model has been explored in both the Newtonian dynamics (as in "kinetic theory") and in quantum mechanics (as a "gas in a box"). The ideal gas model has also been used to model the behavior of electrons in a metal (in the Drude model and the free electron model), and it is one of the most important models in statistical mechanics.
However, the ideal gas law is a good approximation for most gases under moderate pressure and temperature. This law has the following important consequences: If temperature and pressure are kept constant, then the volume of the gas is directly proportional to the number of molecules of gas. If the temperature and volume remain constant, then ...
Therefore, the kinetic energy per kelvin of one mole of monatomic ideal gas (D = 3) is = =, where is the Avogadro constant, and R is the ideal gas constant. Thus, the ratio of the kinetic energy to the absolute temperature of an ideal monatomic gas can be calculated easily:
where V m is the molar volume of an ideal gas at the specified temperature and pressure, which can be chosen freely and must be quoted with values of the Loschmidt constant. The Loschmidt constant is exactly defined for exact temperatures and pressures since the 2019 revision of the SI.
The Rüchardt experiment, [1] [2] [3] invented by Eduard Rüchardt, is a famous experiment in thermodynamics, which determines the ratio of the molar heat capacities of a gas, i.e. the ratio of (heat capacity at constant pressure) and (heat capacity at constant volume) and is denoted by (gamma, for ideal gas) or (kappa, isentropic exponent, for real gas).
where R is the ideal gas constant. According to Mayer's relation, the molar heat capacity at constant pressure would be c P,m = c V,m + R = 1 / 2 fR + R = 1 / 2 (f + 2)R. Thus, each additional degree of freedom will contribute 1 / 2 R to the molar heat capacity of the gas (both c V,m and c P,m).