The word peroxide is used very broadly within the field of chemistry in order to be able to name those oxides that have a higher number of oxygen . Remember that oxides are all compounds that are formed by the combination of oxygen with a metal or with a metalloid.
What are peroxides?
The peroxides are basically those oxides in which can be found a higher proportion of oxygen within the molecule and where two oxygen atoms are intertwined with each other.
- Characteristics of peroxides
- Who discovered them
- Types of peroxides
- Effects edit
- Where they are
- How peroxides are formed
- Examples of peroxides
Characteristics of peroxides
Among the main characteristics of peroxides we mention the following:
- They can be named following the rules of traditional nomenclature, which indicates that the word peroxide will be placed first and then the metallic element, always taking into account the valence.
- Its oxygen atoms bind thanks to a link type covalent .
- They also have two electrons that are not attached and two negative charges.
- They have the ability to behave as oxidizing substances .
- They can cause major fires if they come into contact with combustible materials.
- Its name is obtained by reading the formula from right to left .
- It is considered as a hydride derivative .
Hydrogen peroxide was first identified in 1818 when Louis Jacques Thénard reacted barium peroxide with nitric acid. An improved version of this process used hydrochloric acid , followed by sulfuric acid to accelerate the barium chloride by-product. The Thénard process was used from the end of the 19th century to the middle of the 20th century. And with the passage of time modern manufacturing methods have evolved significantly, making this substance an elemental component of many products .
Who discovered them
Its discovery was made for the first time by LJ Thénard , a French chemist in 1818 . His discovery was based on research into the way some acids acted in barium peroxide.
Types of peroxides
There are the following types of peroxides:
- Organic peroxides : they are a type of organic compound formed by the functional group peroxide and are used for the process known as polymerization which gives rise to plastic polymers, so their use is basic in the creation of plastics such as polystyrene.
- Inorganic peroxides : they are formed by the binary combinations of oxygen and metals. They have a peroxide ion structure, which is also known by the name of dioxide.
Among its physical properties we find that peroxide is usually a liquid that has no color and also has a consistency similar to that of syrup. It has a total density of 1,443 g / cm3. It can form crystals when it is at a temperature that has the ability to melt , approximately -0.89 ° C, and can also boil at 151.4 ° C under normal pressure conditions.
It can also be dissolved when faced with liquids such as alcohol , water and ether regardless of the proportion. When it is diluted it is known by the name of hydrogen peroxide which has a quite astringent and harsh taste.
Regarding the chemical properties of peroxides, they are not very stable. When they are at low temperatures, it can be decomposed and if dust particles are added, this process can be accelerated generating an exothermic reaction . All solutions that are diluted in hydrogen peroxide can be very well preserved and substances such as alcohol, ether and acetanilide work well as preservatives and also make them more stable.
The formula that is generally used to represent peroxides is A 2 (O 2 ) n , where A represents the metallic element and n represents the oxidation number . It is important to mention that this formula cannot be simplified to the maximum, this because it must always have an even number of atoms that correspond to oxygen. There are some important rules when it comes to formulation:
- When n equals 1 , then the peroxide formula will be A 2 O 2 .
- When n is equal to 2 , then its formula should be written as A 2 (O 2 ) When it is simplified then it will remain as AO 2 .
- When n is equal to 3, the formula must be written as A 2 (O 2 ) 3 and in this case, it cannot be simplified.
The structure of peroxides is formed by a bond of oxygen-oxygen in which the oxygen is in oxidation state , in other words -1. In its structure there are also compounds that are formed by the group called peroxo .
One of the most important uses of peroxides is disinfection , because when they release oxygen, it can act against bacteria, eliminating them. You can then disinfect surfaces very easily. In the field of medicine it is also used for this purpose and is generally known by the name of hydrogen peroxide .
It is also used as a solvent for paints that have very bright colors and also acts as a reducer. Another of its uses is to bleach the cotton fibers of fabrics such as wool, linen and silk. It is a powerful oxidant used in the manufacture of Niacin and is an important component of some medications and dyes .
When humans come into contact with peroxides, they can produce various types of side effects, among which we can mention irritation to the eyes , the respiratory tract and also to the skin . When ingested , serious gastrointestinal problems can occur . All the effects that it can produce will also depend on the amount and exposure to which the person is exposed.
Where they are
In general, they can be found in small amounts in the air , water , rain and snow , however, most of them are manufactured by humans since it is a mainly manufactured substance.
How peroxides are formed
Peroxides can be formed when a basic oxide and oxygen combine . Some of them have their origin in the moment in which a substance is exposed with the oxygen present in the air , either in an assisted way or without there being any type of catalyst that forms it. Sometimes they can be formed by reacting hydrogen peroxide with an alkylsulfate.
Their main importance is related to their use as antioxidants and for this reason, they turn out to be fundamental in the pharmaceutical industry , in the food industry and in the hospital field . It is also a very important component in the treatment of wastewater, in the containers that are manufactured to store food or substances, in the purification of water and in the bottling of beverages.
Examples of peroxides
Some examples of peroxides are mentioned below:
- Potassium Peroxide K2O2
- Strontium Peroxide Sr2 (O2) 2
- Rubidium Peroxide Rb2O2
- Barium Peroxide Ba2 (O2) 2
- Aluminum Peroxide Al2 (O2) 3
- Hydrogen Peroxide H2O2