SEPARATION OF SUBSTANCES (post 1)

 GOOD MORNING!!! 

In the previous lesson we understood how to categorize materials into groups. In the current lesson we will talk about methods to separate these substances.

After the blog, you will be able to:
1. Define mixtures.
2. Classify mixtures into Heterogenous and Homogenous mixtures.3. Write the differences between Pure and Impure substances.

Important Note: The text in blue color is to be written in your notebook. 

To begin with, let us know what are the things which needs to be Separated.

MIXTURES

Definition: Materials which contain two or more substances in any proportion are called mixtures.

In simple language: Mixtures are made up of two or more different kinds of particles.

MIXTURES CAN BE SOLID, LIQUID AND GAS.

DO THE QUESTIONS WRITTEN IN RED IN YOUR NOTEBOOK

Q 1. What are mixtures?
Ans

1

Definition: The various substances present in a mixture are called its COMPONENTS or CONSTITUENTS.

E.g. In a mixture of sand, sugar, salt and chalk powder---> Sand, sugar, salt, and chalk powder are components of the mixture.

MIXTURES ARE CLASSIFIED INTO:

Q2.  Differentiate between

ans: a) HOMOGENOUS AND HETEROGENOUS MIXTURES:

Homogeneous mixture	Heterogeneous mixture
1. ‘Homo’ means same	1. ‘Hetero’ means different
2. It has uniform composition	2. It has non uniform composition
3. It can’t be separated physically	3. It can be separated physically
4. Examples of homogeneous mixtures are: salt in water, sugar in water, air, etc.	4. Examples of heterogeneous mixtures are: water and sand, oil and water, sand and clay.

b) PURE AND IMPURE SUBSTANCES

PURE SUBSTANCES	IMPURE SUBSTANCES
1. The substances which have a definite composition.	1. The substances which have indefinite composition.
2. It contains particles of only one type.	2. It contains impurities of different types
3. It has fixed melting or boiling point.	3. It does not have a fixed mixed or boiling point.
4. It has a characteristic taste, colour and odour.	4. The impurities change one or more properties of the substances.
5. For example: pure iron, pure gold, pure oxygen, etc.	5. For example: vegetable soup, muddy water, etc.

ALL BOYS SHOULD DO THE ABOVE  TWO QUESTIONS-ANSWERS IN THEIR NOTEBOOKS

Let us see this activity to see what changes impurities bring into a substance.

Pay heed to the Conclusive points at the end!

 This is all for today!! 

 BYE