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Classification System For Different Types Of Substances

The whole universe is made up of one or the other kind of matter. These matters are nothing but something that has mass and occupies space. Therefore everything around us like plants, tables, clothes, snacks, etc. are all considered a matter.

Although everything around us is a matter, this matter has a broad classification as the things around us are not all the same. The matter is classified into:

  • Pure substances 
  • Mixtures 

What Are Pure Substances?

The term is a very common one related to our daily lives. Usually, pure substances are called substances only. Pure substances are the simplest form of matter that exists. The matter that is made up of only one kind of particle or one kind of atom/molecule is defined as a pure substance. Also, the term itself explains the same where pure means only one kind. Moreover, pure substances are also defined as chemical compositions which have a fixed composition. 

The common exams of pure substances are gold, silver, iron, etc.

PURE SUBSTANCES

The pure substances are subdivided into two types on the basis of chemical compositions:

  • Elements

Elements is a subdivision of the pure substance which is made of a single kind of atom and can not be further broken down into a much simpler substance. These elements are such that on applying either physical or chemical processes, none can break it into a more simple substance as in the case of a gold piece which if broken into pieces still remains the same gold piece.

The elements possess properties like they are homogeneous in nature as in the case of pure silver where only silver atoms are present and no other, or the elements have high melting and boiling points, etc. 

Examples of elements are gold, silver, etc.

The elements are further categorised into:

  • Metals: Metals are elements which easily lose electrons. For example: aluminium, iron etc. They are lustrous, good conductors, malleable, ductile and sonorous.
  • Non- Metals: Non metals are elements which easily gain electrons to become stable. For example, oxygen, chlorine. These non metals are non-lustrous, easily breakable, have low density etc.
  • Metalloids : the elements which possess the properties of both metals as well as non metals are called metalloids. For example, silicon, boron etc. they are basically called amphoteric in nature.
  • Noble gases: noble gases are those elements which do not react and have completely filled the outermost shell. For example: neon, argon etc.
  • Compounds

A compound is a type of pure substance which is formed chemically by the combination of two or more substances but in a fixed proportion. Compounds basically tend to be homogeneous in nature, and cannot be separated into simpler substances by physical processes but chemical processes like electrolysis are applicable for the separation. 

The basic example of a compound is water where all molecules are of water only and on applying a chemical process like electrolysis it splits into two different substances that are hydrogen and oxygen.

Compounds are also further divided into:

  •  Organic : organic substances are those substances which are formed by combination of carbon-hydrogen bonds. 
  • Non-Organic: non organic compounds are the one which do not have the carbon-hydrogen bonding.

The compounds are generally homogeneous, possess definite composition and have sharp melting as well as boiling points.

What Are Mixtures?

Mixtures are the type of matter which form by mixing more than one kind of atom, particle, or substance. Moreover, the mixing must be a physical process where no new product is formed chemically but only the substances are mixed with each other simply. These mixed substances do not tend to lose their individuality as no chemical process is formed.

Some examples of mixtures are sand in water, stones, and sand.  

MIXTURES

  • Homogeneous: Homogeneous mixtures are the mixtures in which the different substances are mixed together but uniformly.

Some examples of homogeneous examples are salt solution, air etc. 

  • Heterogeneous: heterogeneous mixtures are those mixtures in which the different substances are mixed but the composition is not uniform throughout.
  • Some examples of the heterogeneous mixtures are: a solution of salt and sugar where the composition is not uniform.

Conclusion

Therefore every single thing in the universe is made of some kind of substances which are classified into different categories. The science of classification of substances is very vast and the above mentioned were just the basics of the classification. Therefore matter in this universe comprises two kinds which are elements and mixtures. On one hand where elements are made of a single kind and are not separated or broken further by any physical or chemical process, on other hand the mixtures are formed of more than one substance and these mixtures can be separated by either physical processes or chemical processes.

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What is a substance?

A substance is a very general term used in our daily lives. But in physical science, the term ‘substance’ is def...Read full

What are mixtures?

Mixtures are the type of matter which form by mixing more than one kind of atom, particle, or substance. Moreover, t...Read full

What is the classification of a substance?

A pure substance is subdivided into two types which are elements and compounds. Elements and compounds are further s...Read full

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