In Previous chapter we learn about the matter, and physical nature about matter, that is solid, liquid gaseous form. Every things around us are made-up of particles. In this chapter we learn about the things which is present and used in our daily life are that is milk, ghee, salt, spices, mineral water, or juice we buy from the market is pure or not?
- Have You notice that pure written on the package or on the box when we buy from the market?
- For a common men pure means having no, adulteration, or any artificial colour, sweetener, etc.
- But in chemistry or science all these things are mixture of different different components so that is why all these things are not pure.
- For example, Milk is a mixture of different constituents like, Fat, Protein, Water etc. so milk is not Pure Substance.
Matter are classified into two type a) Pure Substances b) Mixture (Impure Substances.
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Pure Substances
Those substances are made up of one type or identical particles are called Pure substances.
(Or)
A homogenous materials Which contains Only one kind of particles and has a chemically definite set of properties is called Pure substances.
Example: Iron, Silver, Gold, Oxygen, sulphur, Carbon dioxide etc.
Characteristics of Pure substances:
- A pure substance is homogenous in nature.
- The composition of pure substances can not be change by any simple physical means.
- A pure substance has definite set of properties.
- All constituents particles are same chemical in nature
- It has fixed boiling and melting point.
Question Answer:
1) What is Pure substance?
Answer: A homogenous materials Which contains Only one kind of particles and has a chemically definite set of proportion is called Pure substances.
2) Explain the characteristics of pure substance?
Answer: Characteristics of pure substance are following.
- A pure substance is homogenous in nature.
- The composition of pure substances can not be change by any simple physical means.
- A pure substance has definite set of properties.
- All constituents particles are same chemical in nature
- It has fixed boiling and melting point.
3) Write down the example of Pure Substances?
Answer: Example of Pure substances are Iron, Silver, Gold, Oxygen, sulphur, Carbon dioxide etc.