| Values of R | Units
(V·P·T-1·n-1) | | 8.314472 | J·K-1·mol-1 | | 0.0820574587 | L·atm·K-1·mol-1 | | 8.20574587 × 10-5 | m3·atm·K-1·mol-1 | | 8.314472 | cm3·MPa·K-1·mol-1 | | 8.314472 | L·kPa·K-1·mol-1 | | 8.314472 | m3·Pa·K-1·mol-1 | | 62.3637 | L·mmHg·K-1·mol-1 | | 62.3637 | L·Torr·K-1·mol-1 | | 83.14472 | L·mbar·K-1·mol-1 | | 1.987 | cal·K-1·mol-1 | | 6.132440 | lbf·ft·K-1·g·mol-1 | | 10.7316 | ft3·psi· °R-1·lb-mol-1 | | 0.7302 | ft3·atm·°R-1·lb-mol-1 | | 1716 | ft·lb·°R-1·slug-1 | | 286.9 | N·m·kg-1·K-1 | | 286.9 | J·kg-1·K-1 | | 999 | ft3·mmHg·K-1·lb-mol-1 | The gas constant (also known as the molar, universal, or ideal gas constant, usually denoted by symbol R) is a physical constant which is featured in a large number of fundamental equations in the physical sciences, such as the ideal gas law and the Nernst equation. It is equivalent to the Boltzmann constant, but expressed in units of energy (i.e. the pressure-volume product) per kelvin per mole (rather than energy per kelvin per particle). Isotherms of an ideal gas The ideal gas law is the equation of state of a hypothetical ideal gas, first stated by Benoît Paul Émile Clapeyron in 1834. ...
The joule (IPA: or ) (symbol: J) is the SI unit of energy. ...
The liter (spelled liter in American English and litre in Commonwealth English) is a unit of volume. ...
Standard atmosphere (symbol: atm) is a unit of pressure. ...
For other uses, see Kelvin (disambiguation). ...
The mole (symbol: mol) is the SI base unit that measures an amount of substance. ...
For other uses, see Pascal. ...
For other uses, see Pascal. ...
One way of defining pressure is in terms of the height of a column of fluid that may be supported by that pressure; or the height of a column of fluid that exerts that pressure at its base. ...
Etymology: French calorie, from Latin calor (heat), from calere (to be warm). ...
In physics, a foot-pound (symbol ft·lbf or ft·lbf) is an Imperial and U.S. customary unit of mechanical work, or energy, although in scientific fields one commonly uses the equivalent metric unit of the joule (J). ...
For the idealized thermodynamic cycle for a steam engine, see Rankine cycle. ...
The mole (symbol: mol) is the SI base unit that measures an amount of substance. ...
For other meanings, see Slug (disambiguation) The slug is an English and U.S. customary unit of mass. ...
In physics, a physical constant is a physical quantity of a value that is generally believed to be both universal in nature and not believed to change in time. ...
Isotherms of an ideal gas The ideal gas law is the equation of state of a hypothetical ideal gas, first stated by Benoît Paul Émile Clapeyron in 1834. ...
In electrochemistry, the Nernst equation gives the electrode potential (E), relative to the standard electrode potential, (E0), of the electrode couple or, equivalently, of the half cells of a battery. ...
The Boltzmann constant (k or kB) is the physical constant relating temperature to energy. ...
For other uses, see Kelvin (disambiguation). ...
The mole (symbol: mol) is the SI base unit that measures an amount of substance. ...
Its value is:
- R = 8.314472(15) J · K-1 · mol-1
The two digits in parentheses are the uncertainty (standard deviation) in the last two digits of the value. For technical reasons, :) and some similar combinations starting with : redirect here. ...
In probability and statistics, the standard deviation of a probability distribution, random variable, or population or multiset of values is a measure of the spread of its values. ...
The gas constant occurs in the simplest equation of state, the ideal gas law, as follows: In physics and thermodynamics, an equation of state is a relation between state variables. ...
Isotherms of an ideal gas The ideal gas law is the equation of state of a hypothetical ideal gas, first stated by Benoît Paul Émile Clapeyron in 1834. ...
 where - P is the pressure
- T is (absolute) temperature
- V is the volume the gas occupies
- n is the amount of gas (loosely number of moles)
- Vm is the molar volume
The gas constant has the same units as specific entropy. This article is about pressure in the physical sciences. ...
Thermodynamic temperature is the absolute measure of temperature and is one of the principal parameters of thermodynamics. ...
In chemistry, the molar volume of a substance is the ratio of the volume of a sample of that substance to the amount of substance (usually in mole) in the sample. ...
For other uses, see: information entropy (in information theory) and entropy (disambiguation). ...
[edit] Relationship with the Boltzmann constant The Boltzmann constant kB (often abbreviated k) may be used in place of the gas constant by working in pure particle count, N, rather than number of moles, n, since The Boltzmann constant (k or kB) is the physical constant relating temperature to energy. ...
 , where NA is Avogadro's number. For example, the ideal gas law in terms of Boltzmann's constant is PV = NkBT. The Avogadro constant (symbols: L, NA), also called the Avogadro number and, in German scientific literature, sometimes also known as the Loschmidt constant/number, is formally defined to be the number of entities in one mole,[1][2] that is the number of carbon-12 atoms in 12 grams (0. ...
[edit] Specific gas constant The specific gas constant of a gas or a mixture of gases ( ) is given by the universal gas constant, divided by the molar mass (M) of the gas/mixture. Molar mass is the mass of one mole of a chemical element or chemical compound. ...
 It is common to represent the specific gas constant by the symbol R. In such cases the context and/or units of R should make it clear as to which gas constant is being referred to. For example, the equation for the speed of sound is usually written in terms of the specific gas constant. This page is about the physical speed of sound waves in a medium. ...
The specific gas constant of dry air is Look up air in Wiktionary, the free dictionary. ...
[edit] US Standard Atmosphere The US Standard Atmosphere, 1976 (USSA1976) defines the Universal Gas Constant as:[1][2] The U.S. Standard Atmosphere is a series of models that define values for atmospheric temperature, density, pressure and other properties over a wide range of altitudes. ...
 The USSA1976 does recognize, however, that this value is not consistent with the cited values for the Avogadro constant and the Boltzmann constant.[2] This disparity is not a significant departure from accuracy, and USSA1976 uses this value of R for all the calculations of the standard atmosphere. When using the ISO value of R, the calculated pressure increases by only 0.62 pascals at 11,000 meters (the equivalent of a difference of only 0.174 meters – or 6.8 inches) and an increase of 0.292 pascals at 20,000 meters (the equivalent of a difference of only 0.338 meters – or 13.2 inches). “ISO†redirects here. ...
[edit] See also The Boltzmann constant (k or kB) is the physical constant relating temperature to energy. ...
[edit] References - ^ Standard Atmospheres. Retrieved on 2007-01-07.
- ^ a b U.S. Standard Atmosphere, 1976, U.S. Government Printing Office, Washington, D.C., 1976 (Linked file is 17 MiB).
Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ...
is the 7th day of the year in the Gregorian calendar. ...
[edit] External links As a non-regulatory agency of the United States Department of Commerce’s Technology Administration, the National Institute of Standards (NIST) develops and promotes measurement, standards, and technology to enhance productivity, facilitate trade, and improve the quality of life. ...
As a non-regulatory agency of the United States Department of Commerce’s Technology Administration, the National Institute of Standards (NIST) develops and promotes measurement, standards, and technology to enhance productivity, facilitate trade, and improve the quality of life. ...
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