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The Kilner Jar was originally invented by John Kilner (1792–1857) and associates, [4] and made by a firm of glass bottlemakers from Yorkshire called Kilner which he set up. [5] The original Kilner bottlemakers operated from 1842, when the company was first founded, until 1937, when the company went into liquidation.
Liquid oxygen has a clear cyan color and is strongly paramagnetic: it can be suspended between the poles of a powerful horseshoe magnet. [2] Liquid oxygen has a density of 1.141 kg/L (1.141 g/ml), slightly denser than liquid water, and is cryogenic with a freezing point of 54.36 K (−218.79 °C; −361.82 °F) and a boiling point of 90.19 K (−182.96 °C; −297.33 °F) at 1 bar (14.5 psi).
When performed on a larger scale, this technique is called freeze-drying, and the cold trap is referred to as the condenser. Cold traps are also used in cryopump systems to generate hard vacua by condensing the major constituents of the atmosphere (nitrogen, oxygen, carbon dioxide and water) into their liquid or solid forms.
Most humans can function at rest with an oxygen level of 15% at one atmosphere pressure; [1] a fuel such as methane is combustable down to 12% oxygen in nitrogen. A small room of 10 meter 3 has 2.08 meter 3 (2080 liters) or 2.99 kg of oxygen which would occupy 2.62 liters if it was liquid. [2]
Chemists remove gases from solvents when the compounds they are working on are possibly air- or oxygen-sensitive (air-free technique), or when bubble formation at solid-liquid interfaces becomes a problem. The formation of gas bubbles when a liquid is frozen can also be undesirable, necessitating degassing beforehand.
This can introduce contaminants. If these materials freeze, for example, water vapor becoming ice, they can block the openings, leading to pressure buildup and the risk of an explosion. Thirdly, the gas escaping from a dewar can gradually displace the oxygen from the air in the surrounding area, which presents an asphyxiation hazard.
Many gases can be put into a liquid state at normal atmospheric pressure by simple cooling; a few, such as carbon dioxide, require pressurization as well. Liquefaction is used for analyzing the fundamental properties of gas molecules (intermolecular forces), or for the storage of gases, for example: LPG , and in refrigeration and air conditioning .
The components of an oxygen absorber vary according to intended use, the water activity of the product being preserved, and other factors. Often the oxygen absorber or scavenger is enclosed in a porous sachet or packet but it can also be part of packaging films and structures. [4] Others are part of a polymer structure. [5]