 Nitrogen
Counting by column, we have now reached the fifth main group. It consists of the non-metals nitrogen and phosphorus, the semi-metals arsenic and antimony and the metal bismuth. As you can see in the picture below,
nitrogen is missing three electrons on the outermost shell.
Nitrogen is a gas and makes up almost four fifths of the air around us. In agriculture, nitrogen is used for fertilization. The chlorophyll needs a certain amount of nitrogen to use it to photosynthesize carbon dioxide and water
into glucose and oxygen, the building blocks of life on earth.
However, if too much nitrogen is added when fertilizing, it can get into the groundwater. In plants, on the other hand, it is referred to as the 'building block of life', as 'essential for life on earth' (Wikipedia). Fillings only with
nitrogen prevent fires when aircraft tires burst.
In the workshop is for welding instead of oxygen and acetylene only one smaller filling with nitrogen remained. Its property is used here to ward off oxygen, e.g. even in the event of fire. For a long time, this could also be very
helpful as a filler for light bulbs.
For a long time, nitrogen oxides played a major role in the automotive sector as a collective term for all compounds of nitrogen and oxygen. They occur with any combustion, the hotter the more. For a long time only diesel
engines were considered the main emitters, but since direct injection it can also affect gasoline engines.
Nitrogen (di)oxide has negative effects on the airways and lungs in humans. It has been under constant surveillance in busy traffic zones for some time. Too much of it in the air can cause partial traffic closures. It is
combated in the engine by exhaust gas recirculation and one or two SCR (Selective Catalytic Reduction) catalytic converters.
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