About 78% of nitrogen gas can be used to make ammonia, nitric acid, nitrate, cyanide, etc. When making explosives; filling high-temperature thermometers and incandescent bulbs; forming inert material preservation materials for drying boxes or glove bags. Liquid nitrogen during food freezing; as a laboratory coolant.

Nitrogen has been widely used in the national economy and daily life. First of all, using its lonely character to charge it into the bulb can prevent the tungsten filament from oxidizing, delay the volatilization of the tungsten filament, and prolong its service life. It can also be used to protect the inert gas when welding metal.

In the museum, some precious and rare pages and scrolls are often stored in cylinders filled with nitrogen, so that the borers can suffocate in the nitrogen. Nitrogen is used to keep the grain in a dormant and hypoxic state, and its metabolism is slow, which can achieve good anti-insect, anti-mildew and anti-deterioration effects. The food is not polluted, the management is simple, the cost is low, and it has developed rapidly in recent years. At present, Japan, Italy and other countries have entered the stage of small-scale production trials. In recent years, many areas in China have also used nitrogen to store grain, called vacuum nitrogen storage grain, and can also be used to store fruits and other agricultural and sideline products.

Using liquid nitrogen to cool the scalpel becomes a cold knife. Doctors use cold knife to perform surgery can reduce bleeding or not, and patients can recover more quickly after surgery. Liquid nitrogen is also very effective in treating patients' skin diseases. This is because the vaporization temperature of liquid nitrogen is -195.8°C, so it often causes skin necrosis and shedding when used to treat surface skin diseases. In the past, dermatologists often used dry ice to treat hemangioma. Although the purpose is the same, the coldness is much lower than that of liquid nitrogen. Artificial pneumothorax in the treatment of tuberculosis also puts nitrogen (or air) into the chest cavity of tuberculosis patients, compresses the diseased lung lobes, and allows them to rest.

Now, people also use the low temperature caused by liquid nitrogen to store the sperm of excellent livestock in various places, and then use it for artificial insemination after thawing. For example, the Guangxi Fisheries Research Institute tried liquid nitrogen to preserve fish and fish semen, and it was successful. Nitrogen is also an important chemical raw material, which can be used to prepare various fertilizers and explosives.

Nitrogen is the foundation of life. It is not only the raw material for chlorophyll from crops, but also the raw material for protein from crops. According to statistics, crops around the world should take in more than 40 million tons of nitrogen from the soil within a year.

Scientists have great hopes for nitrogen. They believe that Rhizobium has a clever way to directly capture nitrogen in the air and turn it into nitrogen fertilizer. It is because there is a nitrogenase in the body, which is an expert in capturing nitrogen. If we can manually synthesize a large amount of ammonia enzymes by chemical methods, can nitrogen easily become nitrogen fertilizer?