Question

What are the characteristic properties of a pure substance? Why do we need them?

Answer 1

Hint: A pure substance is defined as chemical species made up of only one type of atom or one type of molecule. It has uniform composition and appearance. This means it is a substance on its own and is unlike mixtures which have the composition of two or more than two pure substances.

Complete answer:
So, as now we know the definition of a pure substance, let’s move to their characteristic properties.
So, pure substances have a definite set of constant properties such as boiling point, melting point etc. these properties remain uniform throughout the bulk, no matter how small or big the sample is.
Therefore, pure substances are uniform in composition.
Some examples of pure substance – atom, element, iron, pure sugar, diamond, water.
Pure substances are of great importance in day to day life and in industries, like in –
Pure substances are used in the manufacture of many laboratory chemicals.
These are also helpful in the production of medicinal drugs.
Water being the pure substance is one of the most useful and powerful pure substances both in day to day activities and also in laboratories, industries.
Pure substances are of great importance in the scientific research field also.

Note:
Pure substances cannot be broken down into simpler form, no matter what physical method we use. The characteristic property of pure substances like constant boiling temperature and melting temperature makes them a special substance of use.