Gas | Definition, State of Matter, Properties, Structure, & Facts ...
Sep 27, 2024 · Gas, one of the three fundamental states of matter, with distinctly different properties from the liquid and solid states. The remarkable feature of gases is that they appear to have no structure at all. They have neither a definite size nor shape, whereas ordinary solids have both a definite size.
Gas - Molecular, Sizes, Properties | Britannica
Sep 27, 2024 · Gas - Molecular, Sizes, Properties: Molecular sizes can be estimated from the foregoing information on the intermolecular separation, speed, mean free path, and collision rate of gas molecules. It would seem logical that large molecules should have a better chance of colliding than do small molecules.
Gas - Behaviour, Properties, Physics | Britannica
Sep 27, 2024 · Compared to the numbers of molecules involved, there are only a few properties of gases that warrant attention here, namely, pressure, density, temperature, internal energy, viscosity, heat conductivity, and diffusivity.
kinetic theory of gases - Encyclopedia Britannica
Kinetic theory of gases, a theory based on a simplified molecular or particle description of a gas, from which many gross properties of the gas can be derived. Such a model describes a perfect gas and its properties and is a reasonable approximation to a real gas.
Mole | Definition, Number, & Facts | Britannica
Sep 26, 2024 · A mole is defined as 6.02214076 × 10 23 of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.
Atom - Kinetic Theory, Gases, Particles | Britannica
Oct 8, 2024 · The size of the atoms and the distance between them in the gaseous state are related both to the contraction of gas upon liquefaction and to the mean free path traveled by molecules in a gas. The mean free path, in turn, can be found from the thermal conductivity and diffusion rates in the gas.
Gas - Kinetic Theory, Particles, Pressure | Britannica
Sep 27, 2024 · Gas - Kinetic Theory, Particles, Pressure: The aim of kinetic theory is to account for the properties of gases in terms of the forces between the molecules, assuming that their motions are described by the laws of mechanics (usually classical Newtonian mechanics, although quantum mechanics is needed in some cases).
Evaporation | Definition, Water Cycle, & Facts | Britannica
Sep 25, 2024 · Evaporation, process by which an element or compound transitions from its liquid state to its gaseous state below its boiling temperature. It is also how liquid water enters the atmosphere as water vapor, which is an important part of …
Ideal gas | Definition, Equation, Properties, & Facts | Britannica
Oct 12, 2024 · Ideal gas, a gas that conforms, in physical behavior, to a particular idealized relation between pressure, volume, and temperature called the ideal gas law, which states that the product of the volume and pressure is proportional to the absolute temperature.
Liquid | Chemistry, Properties, & Facts | Britannica
Sep 26, 2024 · Liquid, in physics, one of the three principal states of matter, intermediate between gas and crystalline solid. The most obvious physical properties of a liquid are its retention of volume and its conformation to the shape of its container.