Vapour density

Vapour density

Vapour density is the density of a vapour in relation to that of hydrogen. May be defined as mass of a certain volume of a substance divided by mass of same volume of hydrogen.

vapour density = mass of "n" molecules of gas / mass of "n" molecules of hydrogen by definition molar mass of a gas is the ratio of the mass of one molecule of gas to that of an hydrogen atom under similar conditions

so, vapour density = 1/2 molar mass

ee also

*relative density (also known as specific gravity)

In many web sources, the vapour density is defined with respect to air, not hydrogen. With this definition, the vapour density would indicate whether a gas is denser (greater than one) or less dense (less than one) than air. The density has implications for container storage and personnel safety--if a container can release a dense gas, its vapour could sink and, if flammable, collect until it is at a concentration sufficient for ignition. Even if not flammable, it could collect in the lower floor or level of a confined space and displace air, to present a smothering hazard to individuals entering the lower part of that space.

It is recommended that individuals confirm the definition of vapour density being used in their specific context.


Wikimedia Foundation. 2010.

Игры ⚽ Нужна курсовая?

Look at other dictionaries:

  • vapour density — noun the density of a gas relative to the density of hydrogen • Syn: ↑vapor density • Hypernyms: ↑relative density * * * vapour density noun The density of a gas or vapour relative to that of hydrogen at the same temperature and pressure • • •… …   Useful english dictionary

  • vapour density — garų tankis statusas T sritis fizika atitikmenys: angl. vapor density; vapour density vok. Dampfdichte, f rus. плотность пара, f pranc. densité de vapeur, f …   Fizikos terminų žodynas

  • vapour density — noun Chemistry the density of a particular gas or vapour relative to that of hydrogen at the same pressure and temperature …   English new terms dictionary

  • vapour density — /ˈveɪpə dɛnsəti/ (say vaypuh densuhtee) noun 1. the mass which a unit volume of a vapour would possess if it could exist as an ideal gas at 0°C at a pressure of 760 mm of mercury. 2. the ratio of the mass of a given volume of a gas to an equal… …  

  • vapour density — noun The ratio of the density of a gas to the density of hydrogen at the same temperature and pressure …   Wiktionary

  • saturated vapour density — sočiųjų garų tankis statusas T sritis fizika atitikmenys: angl. saturated vapor density; saturated vapour density; steam density vok. Dampfdichte, f; Sättigungsdampfdichte, f rus. плотность насыщенного пара, f pranc. densité de vapeur saturée, f …   Fizikos terminų žodynas

  • Density (disambiguation) — Density and dense usually refer to a measure of how much of some entity is within a fixed amount of space. Types of density include: In physics, density of mass: Density, mass per volume Area density or surface density, mass over a (two… …   Wikipedia

  • vapour — n. & v. (US vapor) n. 1 moisture or another substance diffused or suspended in air, e.g. mist or smoke. 2 Physics a gaseous form of a normally liquid or solid substance (cf. GAS). 3 a medicinal agent for inhaling. 4 (in pl.) archaic a state of… …   Useful english dictionary

  • vapour — Vapor Va por, n. [OE. vapour, OF. vapour, vapor, vapeur, F. vapeur, L. vapor; probably for cvapor, and akin to Gr. ? smoke, ? to breathe forth, Lith. kvepti to breathe, smell, Russ. kopote fine soot. Cf. {Vapid}.] [Written also {vapour}.] [1913… …   The Collaborative International Dictionary of English

  • relative density — noun the ratio of the density of something to the density of a standard • Hypernyms: ↑density, ↑denseness • Hyponyms: ↑specific gravity, ↑vapor density, ↑vapour density * * * ˌrelative ˈdensity 7 [relative dens …   Useful english dictionary

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”