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In chemistry, the term chemically inert is used to describe a substance that is not chemically reactive. From a thermodynamic perspective, a substance is inert, or nonlabile , if it is thermodynamically unstable (positive standard Gibbs free energy of formation ) yet decomposes at a slow, or negligible rate.
Reactive nitrogen ("Nr"), also known as fixed nitrogen [1], refers to all forms of nitrogen present in the environment except for molecular nitrogen (N 2 ). [ 2 ] While nitrogen is an essential element for life on Earth, molecular nitrogen is comparatively unreactive, and must be converted to other chemical forms via nitrogen fixation before it ...
The term inert gas is context-dependent because several of the inert gases, including nitrogen and carbon dioxide, can be made to react under certain conditions. [ 1 ] [ 2 ] Purified argon gas is the most commonly used inert gas due to its high natural abundance (78.3% N 2 , 1% Ar in air) [ 3 ] and low relative cost.
Free nitrogen atoms easily react with most elements to form nitrides, and even when two free nitrogen atoms collide to produce an excited N 2 molecule, they may release so much energy on collision with even such stable molecules as carbon dioxide and water to cause homolytic fission into radicals such as CO and O or OH and H. Atomic nitrogen is ...
In chemistry, a nitrene or imene (R−:Ṅ·) is the nitrogen analogue of a carbene. The nitrogen atom is uncharged and monovalent, [1] so it has only 6 electrons in its valence level—two covalent bonded and four non-bonded electrons. It is therefore considered an electrophile due to the unsatisfied octet.
In organic chemistry, nitration is a general class of chemical processes for the introduction of a nitro group (−NO 2) into an organic compound.The term also is applied incorrectly to the different process of forming nitrate esters (−ONO 2) between alcohols and nitric acid (as occurs in the synthesis of nitroglycerin).
In organic chemistry, neighbouring group participation (NGP, also known as anchimeric assistance) has been defined by the International Union of Pure and Applied Chemistry (IUPAC) as the interaction of a reaction centre with a lone pair of electrons in an atom or the electrons present in a sigma or pi bond contained within the parent molecule but not conjugated with the reaction centre.
About 99% of the Earth's atmosphere is composed of two species of diatomic molecules: nitrogen (78%) and oxygen (21%). The natural abundance of hydrogen (H 2) in the Earth's atmosphere is only of the order of parts per million, but H 2 is the most abundant diatomic molecule in the universe. The interstellar medium is dominated by hydrogen atoms.