UNIT -5

1. SEPARATION OF
SUBSTANCES
BY: MISS RITIMA
APS RAKHMUTHI

2. WHY DO WE SEPARATE SUBSTANCES

3. METHODS OF SEPARATION
 HAND PICKING
THRESHING
WINNOWING
SIEVING
SEDIMENTATION AND DECANTATION
FILTRATION
EVAPORATION

4. HAND PICKING
IT IS USED FOR THE SEPARATION OF THE LARGE
IMPURITIES.
 THE COMPONENTS OF THE SOLID MIXTURE
CAN BE SEPARATED BY HAND PICKING.
EXAMPLE: SEPARATION OF PEBBLES FROM THE
DAL , SEPARATION OF GRASS FROM MINT
.....LEAVES.

5. THREASHING
 THE PROCESS IN WHICH STALKS ARE BEATEN
TO FREE THE GRAINS ISCALLED THREASHING.
 NOW A DAYS MACHINES ARE USED FOR
THREASHING.

6. WINNOWING
 IT IS THE PROCESS USED TO SEPARATE HEAVIER
AND LIGHTER COMPONENTS OF THE MIXTURE BY
WIND OR BLOWING AIR.
THIS METHOD IS USED BY THE FARMERS TO
SEPARATE LIGHTER HUSK PARTICLES FROM
HEAVIER SEEDS OF THE GRAINS.

7. SIEVING
 IT IS A PROCESS IN WHICH THE COMPONENTS
OF A MIXTURE WITH DIFFERENT SIZE ARE
SEPARATED WITH THE HELP OF THE SIEVE.
THE SMALLER PARTICLES ARE PASSED
THROUGH THE PORES OF THE SIEVE AND THE
LARGER PARTICLES ARE LEFT BEHIND.
THIS METHOD IS USED TO SEPARATE BRAN
FROM FLOUR.

8. SEDIMENTATION
SEDIMENTATION IS THE PROCESS OF
SEPARATION OF TWO COMPOENTS IN SUCH A
WAY THAT HEAVIER COMPONENTS SETTLES
DOWN.

9. DECANTATION
DECANTATION IS THE PROCESS OF SEPARATION
OF LIQUID FROM SOLID OR OTHER IMMISCIBLE
LIQUIDS BY REMOVING LIQUID LAYER AT TOP
FROM LAYER OF SOLID OR LIQUID BELOW.
 EXAMPLE: SEPARAION
OF SAND AND WATER BY
DECANTATION.

10. FILTRATION
 IN THIS PROCESS THE SEPARATION OF SOLID
FROM LIQUID DONE BY FILTER PAPER.
EXAMPLE: SEPATION OF MUD FROM WATER
USING FILTER PAPER.

11. EVAPORATION
THIS PROCESS IS USED WHEN WE WANT TO GET
BACK THE SUBSTANCE THAT IS DISSOVED.
 IN THIS PROCESS THE LIQUID CHANGES INTO
GASEOUS FORM WHEN HEATED.
EXAMPLE: GETTING SALT FROM SEA WATER.