Active nitrogen - Catalytic nitrogen

When a discharge occurs in nitrogen gas, the nitrogen becomes chemically active. This gas is called active nitrogen. It is extremely reactive, and forms azides or nitrides with many metals, including alkali metals, calcium, magnesium, mercury, aluminum, and cobalt. It also reacts violently with organic compounds to form hydrogen cyanide. In addition to free nitrogen atoms, active nitrogen also contains many nitrogen molecules in an excited state. Active nitrogen emits a yellow-orange light. This emission has a long lifespan, and can be observed even after the discharge has stopped, depending on the conditions. This is called discharge afterglow.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

窒素気体中で放電を行うと，窒素は化学的に活性な性質をもつようになる．この気体を活性窒素という．反応性がきわめて強く，アルカリ金属，カルシウム，マグネシウム，水銀，アルミニウム，コバルトなど多くの金属とアジ化物あるいは窒化物をつくる．有機化合物ともはげしく反応して，シアン化水素をつくる．活性窒素中には遊離した窒素原子のほか，励起状態にある窒素分子も多く存在する．活性窒素では黄橙色の発光が見られる．この発光の寿命は長く，放電停止後も条件によっては観測できる．これを放電後残光という．

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