AP 6th Class Science Notes Chapter 5 Materials: Separating Methods

→ Objects around us are made of a large variety of materials.

→ Based on their properties, we use different materials for different purposes. Materials can exist in three important states; solids, liquids, and gases.

→ Some materials change their state from solid to liquid, liquid to gas on being heated, and from gas to liquid, liquid to solid on being cool.

→ Some materials sink in water and some materials can float on water.

→ Some materials in one shape will sink in water but float on water when they are in another shape.

→ Some materials are soluble in water and some materials are insoluble in water.

→ The materials that can dissolve are said to be insoluble.

→ The materials that do not dissolve are said to be insoluble.

→ Materials are grouped together on the basis of similarities and differences in their properties.

→ A combination of more than one substance forms a mixture.

→ Substances can be separated from a mixture.

→ Hand-picking is used to separate substances when their sizes are sufficiently large.

→ If mixtures have light and heavy substances, winnowing can be used for separation.

→ An insoluble substance in a liquid can be separated by sedimentation and decantation.

→ Sieving can be used for separating larger and smaller substances in a mixture.

     My Class Notes

→ Crystallization is used for the separation of dissolved substances from a liquid.

→ Distillation is used to remove impurities from water.

→ More than one method of separation can be used to separate the components of some mixtures.

→ Material: The substance used to make things is called material Ex: Wood, Metal, rock, cotton, etc.

→ Object: AnythIng that has a fixed shape that you can touch or see and that is not alive is called an Object. Ex: Chair, book, ring, board, etc.

→ Metal: Any class of mineral substance which has lustrous, a good conductor of heat, electricity and usually hard is called “metal. Ex: Gold, silver, copper, iron, etc.”

→ Solid: A substance that has a definite shape is called “Solid”. Ex: Sand, salt, rock, brick.

→ Liquid: A substance that flows, can be poured, and takes the shape of the container is called “liquid”. Ex: Water, oil.

→ Gas: A substance like the air that ¡s neither Liquid nor solid is called “gas”. Ex: Air, smoke, water vapor, oxygen, etc.

→ Sink: Go down below the surface of water or any other liquid.

→ Float: Move slowly on water or in the air.

→ Soluble: That can be dissolved in water or any other liquid.

→ Insoluble: That does not dissolve in water any other liquid.

→ Mixture: A combination of more than one substance is called a “Mixture”.

→ Separation: Divide into parts or groups.

→ Hand-picking: Chosen from a lot by hand.

→ Winnowing: The method of separating components of a mixture by wind or by blowing air. Ex: Husk from the grains.

→ Sedimentation: The process of settling or being deposited to the bottom.

→ Decantation: The separation of the clear upper liquid from the sediment (the separation of mixtures of immiscible liquids or of a liquid and a solid mixture)

→ Sieving: The method used to separate fine particles from large particles in a mixture by using a sieve.

     My Class Notes

→ Filtration: The process used to separate solids from liquids or gases using a filter medium (Filter paper, Cloth, etc. witch has minute pores) that allows the fluid to pass through but not the solid.

→ Crystallization: The process used to separate dissolved solid substances from a liquid by transforming them into crystals.

→ Distillation: The process used to remove impurities from liquids by boiling

→ Sublimation: The process in which a matter changes directly from solid to gaseous form and vice-versa.

→ Chromatography: A process of separating the component of the mixture by selective absorption of various compounds as identIfiable bands.

→ A solvent Is a liquid that dissolves other substances in it. Water can dissolve more substances than any other solvents. So it is called Universal Solvent.

→ Farmers separate grains which are bigger in size from the smaller ones by sieving. The bigger grains are then used as seeds or sold at a higher price.