Introduction
If you look closely at nitrogen in the periodic table 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 discovered recently, and some have been studied far and wide. There are unstable and stable nitrogen oxides. The chemical properties of each of these substances are completely different, so at least five oxides of nitrogen must be considered when studying them. That's about them and will be discussed in today's article.
Nitric oxide (I)
Formula - N2O. It may sometimes be referred to as nitrogen oxonitride, dinitrous oxide, nitrous oxide, or laughing gas.
Properties
Under normal conditions, it is a colorless gas with a sweetish odor. It can be dissolved by water, ethanol, ether and sulfuric acid. If the gaseous oxide of monovalent nitrogen is heated to room temperature under a pressure of 40 atmospheres, then it thickens to a colorless liquid. It is a non-s alt-forming oxide that decomposes when heated and shows itself in reactions as a reducing agent.
Receive
This oxide is formed,when dry ammonium nitrate is heated. Another way to obtain it is the thermal decomposition of a mixture of "sulfamic + nitric acid".
Application
Used as an inhalation anesthetic, the food industry knows this oxide as additive E942. It also improves the performance of internal combustion engines.
Nitric oxide (II)
Formula - NO. Occurs under the names of nitric monoxide, nitric oxide and nitrosyl radical
Properties
Under normal conditions, it is a colorless gas that 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
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It is quite easy to get, for this you need to heat up to 1200-1300oC mixture of nitrogen and oxygen. In laboratory conditions, it is formed immediately in several experiments:
- Reaction of copper and 30% nitric acid solution.
- Reaction 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 obtained.
Nitric oxide (III)
The formula is N2O3. It may also be called nitrous anhydride and nitrogen sesquioxide.
Properties
Under normal conditions, it is a liquid that has a bluecolor, and in standard - colorless gas. Pure oxide exists only in a solid state of aggregation.
Receive
Produced 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 s alts are obtained in laboratories.
Nitric oxide (IV)
The formula is NO2. It may also be called nitrogen dioxide or brown gas.
Properties
The last name corresponds to one of its properties. After all, this oxide has the appearance of either a red-brown gas or a yellowish liquid. It has a high chemical activity.
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This oxide is produced by the interaction of nitric acid and copper, as well as during the thermal decomposition of lead nitrate.
Application
It is used to produce sulfuric and nitric acids, oxidize liquid rocket fuel and mixed explosives.
Nitric oxide (V)
Formula - N2O5. May occur under the names dianitrogen pentoxide, nitroyl nitrate, or nitric anhydride.
Properties
It has the appearance of colorless and very volatile crystals. They can melt at 32.3oC.
Receive
This oxide is formed by several reactions:
- Dehydration of nitric acid with pentavalent phosphorus oxide.
- Passing dry chlorine over silver nitrate.
- Interaction of ozone with tetravalent nitrogen oxide.
Application
Due to its extreme instability, it is not used in its pure form anywhere.
Conclusion
There are nine oxides of nitrogen in chemistry, 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 he alth of people living near industrial chemical enterprises. Symptoms of poisoning with any of these substances are toxic pulmonary edema, disruption of the central nervous system, and blood damage caused by hemoglobin binding. Therefore, nitrogen oxides must be handled with care and protective equipment used in most cases.
