
Pressure | Definition, Measurement, & Types | Britannica
Nov 12, 2025 · Absolute pressure of a gas or liquid is the total pressure it exerts, including the effect of atmospheric pressure. An absolute pressure of zero corresponds to empty space or a …
Gas laws | Definition & Facts | Britannica
Sep 24, 2025 · Boyle’s law —named for Robert Boyle —states that, at constant temperature, the pressure P of a gas varies inversely with its volume V, or PV = k, where k is a constant.
Gas | Definition, State of Matter, Properties, Structure, & Facts ...
Oct 15, 2025 · The pressure exerted by a gas is the result of the innumerable impacts of the molecules on the container walls and appears steady to human senses because so many …
Ideal gas law | Definition, Formula, & Facts | Britannica
Nov 7, 2025 · Ideal gas law, relation between the pressure P, volume V, and temperature T of a gas in the limit of low pressures and high temperatures, such that the molecules of the gas …
Boyle’s law | Definition, Equation, & Facts | Britannica
Oct 21, 2025 · Boyle’s law, a relation concerning the compression and expansion of a gas at constant temperature. This empirical relation, formulated by the physicist Robert Boyle in …
Ideal gas | Definition, Equation, Properties, & Facts | Britannica
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 …
Gas - Behaviour, Properties, Physics | Britannica
Oct 15, 2025 · It states that the volume of a gas at constant temperature is inversely proportional to the pressure; i.e., if the pressure on a gas is doubled, for example, its volume decreases by …
Dalton’s law | Definition & Facts | Britannica
Dalton’s law, the statement that the total pressure of a mixture of gases is equal to the sum of the partial pressures of the individual component gases. The partial pressure is the pressure that …
Charles’s law | Definition & Facts | Britannica
Oct 28, 2025 · Boyle’s law —named for Robert Boyle —states that, at constant temperature, the pressure P of a gas varies inversely with its volume V, or PV = k, where k is a constant.
Vapour pressure | Definition & Facts | Britannica
Nov 11, 2025 · Vapour pressure, pressure exerted by a vapour when the vapour is in equilibrium with the liquid or solid form, or both, of the same substance—i.e., when conditions are such …