Search results
Results from the WOW.Com Content Network
Liquid nitrogen is a compact and readily transported source of dry nitrogen gas, as it does not require pressurization. Further, its ability to maintain temperatures far below the freezing point of water, specific heat of 1040 J ⋅kg -1 ⋅K -1 and heat of vaporization of 200 kJ⋅kg -1 makes it extremely useful in a wide range of applications ...
Liquid nitrogen. Nitrogen is a colourless, odourless, and relatively inert diatomic gas with a density of 1.251 × 10 −3 g/cm 3 (marginally heavier than air). It condenses to a colourless liquid at −195.795 °C and freezes into an ice- or snow-like solid at −210.00 °C.
Because the liquid-to-gas expansion ratio of nitrogen is 1:694 at 20 °C, a tremendous amount of force can be generated if liquid nitrogen is rapidly vaporised in an enclosed space. In an incident on January 12, 2006, at Texas A&M University , the pressure-relief devices of a tank of liquid nitrogen were malfunctioning and later sealed.
The only chemical elements that form stable homonuclear diatomic molecules at standard temperature and pressure (STP) (or at typical laboratory conditions of 1 bar and 25 °C) are the gases hydrogen (H 2), nitrogen (N 2), oxygen (O 2), fluorine (F 2), and chlorine (Cl 2), and the liquid bromine (Br 2).
All the elements in the group are solids at room temperature, except for nitrogen which is gaseous at room temperature. Nitrogen and bismuth, despite both being pnictogens, are very different in their physical properties. For instance, at STP nitrogen is a transparent non-metallic gas, while bismuth is a silvery-white metal. [12]
Thus, it is relatively easy to predict the chemical properties of an element if one knows the properties of the elements around it. [9] Today, 118 elements are known, the first 94 of which are known to occur naturally on Earth at present. [10] [a] The remaining 24, americium to oganesson (95–118), occur only when synthesized in laboratories.
Sometimes the old "turn it off and on again" actually works. In this case, try completely signing out of your account then sign back in. Many times, this will help, especially in cases of bad passwords or some simple browser issues.
Homonuclear diatomic molecules include hydrogen (H 2), oxygen (O 2), nitrogen (N 2) and all of the halogens. Ozone (O 3) is a common triatomic homonuclear molecule. Homonuclear tetratomic molecules include arsenic (As 4) and phosphorus (P 4). Allotropes are different chemical forms of the same element (not containing any other element). In that ...