ideal gas

American  

noun

Physics.

1. a gas composed of molecules on which no forces act except upon collision with one another and with the walls of the container in which the gas is enclosed; a gas that obeys the ideal gas law.

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ideal gas British  

noun

1. Also called: perfect gas.  a hypothetical gas which obeys Boyle's law exactly at all temperatures and pressures, and which has internal energy that depends only upon the temperature. Measurements upon real gases are extrapolated to zero pressure to obtain results in agreement with theories relating to an ideal gas, especially in thermometry

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ideal gas Scientific  

/ ī-dē′əl /

1. A hypothetical gas whose molecules bounce off each other (and the boundaries of their container) with perfect elasticity and have negligible size, and in which the intermolecular forces acting between molecules not in contact with each other are also negligible. Such a gas would obey the gas laws (such as Charles's law and Boyle's law) exactly at all temperatures and pressures. Most actual gases behave approximately as ideal gases, except at very low temperatures (when the potential energy of their intermolecular forces is high relative to the kinetic energy of the molecules and becomes significant), and under very high pressures (when the molecules are packed so close together that close-range intermolecular forces become significant).

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Etymology

Origin of ideal gas

First recorded in 1890–95

Example Sentences

"Knowledge of Bernoulli's law, the ideal gas law, and isothermal expansion are the three ingredients we baked into a model to explore how this device worked," Lipscombe said.

From Science Daily • Jan. 23, 2024

What can we learn from this atomic and molecular version of the ideal gas law?

From Textbooks • Aug. 12, 2015

It is used extensively in scientific work because a number of physical quantities, such as the volume of an ideal gas, are directly related to absolute temperature.

From Textbooks • Aug. 12, 2015

The ideal gas law describes the behavior of real gases under most conditions.

From Textbooks • Aug. 12, 2015

Wood.—Fuel and oil gas and the future Utopia of improved gas manufacturing.—The ideal gas company of after days.—A valuable and suggestive paper.

From Scientific American Supplement, No. 648, June 2, 1888. by Various