Introduction
If you take a close look at the nitrogen in the periodic system of chemical elements of D. I. Mendeleev, you will notice that it has a variable valency. This means that nitrogen forms several binary compounds with oxygen at once. Some of them have been recently discovered, and some have been studied up and down. There are unstable and stable nitrogen oxides. The chemical properties of each of these substances are completely different, therefore, when studying them, at least five nitrogen oxides should be considered. This is what they will be discussed in today's article.
Nitric oxide (I)
The formula is N
2 O. Sometimes it can be called nitrogen oxonitride, diazot oxide, nitrous oxide or laughing gas.
The properties
Under normal conditions, it is a colorless gas with a sweet smell. It can be dissolved by water, ethanol, ether and sulfuric acid. If gaseous monovalent nitrogen oxide is heated to room temperature under a pressure of 40 atmospheres, then it thickens to a colorless liquid. It is a non-salt-forming oxide that decomposes during heating and shows itself as a reducing agent in reactions.
Getting
This oxide is formed when dry ammonium nitrate is heated . Another method for its preparation is the thermal decomposition of the sulfamic + nitric acid mixture.
Application
Used as a means for inhalation anesthesia, the food industry knows this oxide as additive E942. It also improves the technical characteristics of internal combustion engines.
Nitric oxide
The formula is NO. It is found under the names of nitric monoxide, nitric oxide and nitrosyl radical
The properties
Under normal conditions, it looks like a colorless gas, which is poorly soluble in water. It is difficult to liquefy, but in solid and liquid states this substance has a blue color. This oxide can be oxidized by atmospheric oxygen.
Getting
It is quite simple to obtain, for this you need to heat a mixture of nitrogen and oxygen to 1200-1300 ° C. In laboratory conditions, it is formed immediately with several experiments:
- The reaction of copper and a 30% solution of nitric acid.
- The interaction of ferric chloride, sodium nitrite and hydrochloric acid.
- The reaction of nitrous and hydroiodic acids.
Application
This is one of the substances from which nitric acid is derived.
Nitric oxide
The formula is N
2 O
3 . It can also be called nitrous anhydride and nitrogen sesquioxide.
The properties
Under normal conditions, it is a liquid that has a blue color, and in standard conditions it is a colorless gas. Pure oxide exists only in the solid state of aggregation.
Getting
It is formed by the interaction of 50% nitric acid and solid oxide of trivalent arsenic (it can also be replaced with starch).
Application
With the help of this substance, nitrous acid and its salts are obtained in laboratories.
Nitric oxide
The formula is NO
2 . It can also be called nitrogen dioxide or brown gas.
The properties
The latter name corresponds to one of its properties. After all, this oxide has the form of either a red-brown gas or a yellowish liquid. High chemical activity is inherent in it.
Getting
This oxide is obtained by the interaction of nitric acid and copper, as well as during the thermal decomposition of lead nitrate.
Application
Using it, sulfuric and nitric acids are produced, liquid rocket fuel and mixed explosives are oxidized .
Nitric oxide (V)
The formula is N
2 O
5 . It can be found under the names of diazot Pentaoxide, nitroyl nitrate or nitric anhydride.
The properties
It has the appearance of colorless and very volatile crystals. They can melt at a temperature of 32.3 about C.
Getting
This oxide is formed in several reactions:
- Dehydration of nitric acid with pentavalent phosphorus oxide.
- The transmission of dry chlorine over silver nitrate.
- The interaction of ozone with tetravalent nitric oxide.
Application
Due to its extreme instability, it is not used anywhere in its pure form.
Conclusion
In chemistry, there are nine nitrogen oxides, the above are only classical compounds of this element. The remaining four are, as already mentioned, unstable substances. However, they all share one property - high toxicity. Emissions of nitrogen oxides into the atmosphere lead to a deterioration in the health status of people living near industrial chemical plants. Symptoms of poisoning with any of these substances are toxic pulmonary edema, disruption of the central nervous system and blood damage, the cause of which is hemoglobin binding. Therefore, nitrogen oxides must be handled with care and, in most cases, the use of protective equipment.