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The The Different Separation Different Separation Techniques are as follows:Techniques are as follows:

~ Magnetic attraction~ Magnetic attraction

~ Filtration~ Filtration

~ Evaporation~ Evaporation

~ Distillation~ Distillation

~ Chromatography ~ Chromatography

~ Sublimation~ Sublimation

~ Using Separating Funnel~ Using Separating Funnel

Note: The physical methods used will Note: The physical methods used will depend on the nature of its depend on the nature of its constituents.constituents.

The The Different Separation Different Separation Techniques are as follows:Techniques are as follows:

~ Magnetic attraction~ Magnetic attraction

~ Filtration~ Filtration

~ Evaporation~ Evaporation

~ Distillation~ Distillation

~ Chromatography ~ Chromatography

~ Sublimation~ Sublimation

~ Using Separating Funnel~ Using Separating Funnel

Note: The physical methods used will Note: The physical methods used will depend on the nature of its depend on the nature of its constituents.constituents.

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This process is used This process is used to to separateseparate

magnetic objectsmagnetic objects e.g. iron, e.g. iron, steel, steel,

nickel, cobalt nickel, cobalt from from non-non-magneticmagnetic

ones in a mixture,ones in a mixture, e.g. e.g. separating separating

iron filings and sulfur powder.iron filings and sulfur powder.

Magnetic AttractionMagnetic Attraction

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1. Electromagnets are used to remove 1. Electromagnets are used to remove steel and iron scrap at the junk-yard.steel and iron scrap at the junk-yard.

2. In hospitals, magnets are often used 2. In hospitals, magnets are often used to remove iron splinters from a patient’sto remove iron splinters from a patient’seyes.eyes.

Applications of Magnetic Applications of Magnetic AttractionAttraction

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Filtration

This process is used to separate insoluble solids from the liquid in a solid-liquid mixture, e.g. separating sand from a mixture of sand and water.

The insoluble solid that remains on the filter paper is called residue. The liquid that passes through is called the filtrate.

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• air filters in air conditioners

remove solid impurities from airremove solid impurities from air

• hair in our nostrils

trap the dust particles that we trap the dust particles that we breathe in and allow only clean breathe in and allow only clean air to pass throughair to pass through

• oil and air filters in cars

remove solid impurities found in remove solid impurities found in engine oil and airengine oil and air

• air filters in air conditioners

remove solid impurities from airremove solid impurities from air

• hair in our nostrils

trap the dust particles that we trap the dust particles that we breathe in and allow only clean breathe in and allow only clean air to pass throughair to pass through

• oil and air filters in cars

remove solid impurities found in remove solid impurities found in engine oil and airengine oil and air

Applications of FiltrationApplications of Filtration

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Evaporation to dryness is a Evaporation to dryness is a process used to process used to separate aseparate a dissolved soliddissolved solid that that does notdoes not decomposedecompose on heating on heating from a solution, e.g. common salt , e.g. common salt from a salt solutionfrom a salt solution

Evaporation to dryness is a Evaporation to dryness is a process used to process used to separate aseparate a dissolved soliddissolved solid that that does notdoes not decomposedecompose on heating on heating from a solution, e.g. common salt , e.g. common salt from a salt solutionfrom a salt solution

Evaporation to Evaporation to drynessdryness

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1.Pour the solution into an evaporating dish.

2.Heat the solution to dryness to evaporate away the solvent, leaving behind the solute.

3.Make the Bunsen flame smaller when almost all the solvent has been evaporated away to reduce spitting.

1.Pour the solution into an evaporating dish.

2.Heat the solution to dryness to evaporate away the solvent, leaving behind the solute.

3.Make the Bunsen flame smaller when almost all the solvent has been evaporated away to reduce spitting.

Evaporating a SolutionEvaporating a Solution

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• drying wet clothes

• drying hair with a hair-dryer

• obtaining common salt from the sea

• drying wet clothes

• drying hair with a hair-dryer

• obtaining common salt from the sea

Applications of EvaporationApplications of Evaporation

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DistillationDistillation is a process used is a process used to separate a to separate a liquid(solvent) liquid(solvent) from a solid-liquid solution or from a solid-liquid solution or liquid-liquid solution.liquid-liquid solution.

Pure water can be distilled from a Pure water can be distilled from a soft drinkssoft drinks

DistillationDistillation is a process used is a process used to separate a to separate a liquid(solvent) liquid(solvent) from a solid-liquid solution or from a solid-liquid solution or liquid-liquid solution.liquid-liquid solution.

Pure water can be distilled from a Pure water can be distilled from a soft drinkssoft drinks

DistillationDistillation

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Distillation

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This process can be used to This process can be used to separate miscible liquids separate miscible liquids with different boiling pointswith different boiling points where the liquid with the where the liquid with the lower lower boiling point will vaporize boiling point will vaporize firstfirst

We can use this method to We can use this method to separate alcohol and waterseparate alcohol and water

This process can be used to This process can be used to separate miscible liquids separate miscible liquids with different boiling pointswith different boiling points where the liquid with the where the liquid with the lower lower boiling point will vaporize boiling point will vaporize firstfirst

We can use this method to We can use this method to separate alcohol and waterseparate alcohol and water

Fractional Fractional DistillationDistillation

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Fractional Distillation

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Chromatography is a process Chromatography is a process used to separate the different used to separate the different components in a liquid or components in a liquid or gaseous mixture.gaseous mixture.

For example it can be used to:

1.Separate the different coloured components that make up black ink

2.Detect tiny amounts of drugs or certain other chemicals in urine samples

Chromatography is a process Chromatography is a process used to separate the different used to separate the different components in a liquid or components in a liquid or gaseous mixture.gaseous mixture.

For example it can be used to:

1.Separate the different coloured components that make up black ink

2.Detect tiny amounts of drugs or certain other chemicals in urine samples

Chromatography

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1.1.Apply a small but Apply a small but concentratedconcentratedspot of the solution on a spot of the solution on a piece of chromatography piece of chromatography paper.paper.

2.2.Suspend the Suspend the chromatographychromatographypaper in a beaker or boiling paper in a beaker or boiling tube of solvent with the spot tube of solvent with the spot above the level of the above the level of the solvent.solvent.

1.1.Apply a small but Apply a small but concentratedconcentratedspot of the solution on a spot of the solution on a piece of chromatography piece of chromatography paper.paper.

2.2.Suspend the Suspend the chromatographychromatographypaper in a beaker or boiling paper in a beaker or boiling tube of solvent with the spot tube of solvent with the spot above the level of the above the level of the solvent.solvent.

Paper Paper ChromatographyChromatography

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Paper Paper ChromatographyChromatography

3.Separation takes place because some components of the liquid mixture travel at a faster pace than other components on the paper or any other absorbent material.

Paper Paper ChromatographyChromatography

3.Separation takes place because some components of the liquid mixture travel at a faster pace than other components on the paper or any other absorbent material.

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Paper Chromatography

4.As the solvent travels up the paper, the mixture is separated into its respective components.

A chromatogram of the separated components is obtained.

Paper Chromatography

4.As the solvent travels up the paper, the mixture is separated into its respective components.

A chromatogram of the separated components is obtained.

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Applications

•Analysing ink dyes for forgery Analysing ink dyes for forgery

casescases

•Analysing food dyes to ensure Analysing food dyes to ensure that that

only permitted colourings are only permitted colourings are used used

in foodstuffsin foodstuffs•Checking whether pesticides Checking whether pesticides on on

vegetables exceed safe levelsvegetables exceed safe levels•Detecting trace levels of drugs Detecting trace levels of drugs in in urine samples urine samples

Applications

•Analysing ink dyes for forgery Analysing ink dyes for forgery

casescases

•Analysing food dyes to ensure Analysing food dyes to ensure that that

only permitted colourings are only permitted colourings are used used

in foodstuffsin foodstuffs•Checking whether pesticides Checking whether pesticides on on

vegetables exceed safe levelsvegetables exceed safe levels•Detecting trace levels of drugs Detecting trace levels of drugs in in urine samples urine samples

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Advantage

•Able to obtain results Able to obtain results quick.quick.

•Only a small amount of Only a small amount of sample is required for sample is required for chromatography.chromatography.

Advantage

•Able to obtain results Able to obtain results quick.quick.

•Only a small amount of Only a small amount of sample is required for sample is required for chromatography.chromatography.

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Using a Separating Using a Separating FunnelFunnel

A separating funnel can be used to separate two immiscible two immiscible liquidsliquids, such as oil and water.

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SublimationSublimationThis method is used to separate a solid which sublimes when solid which sublimes when heatedheated.

Common substances which can sublime include iodine, dry ice, mothballs (napthalene) and ammonium chloride.

A mixture containing ammonium chloride and sodium chloride can be separated using this method.

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Techniques in obtaining Techniques in obtaining Pure Water from Sea Pure Water from Sea

WaterWaterMethod 1

• Distillation of sea water.

Method 2

•Desalination of sea water by Reverse Osmosis

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Reverse OsmosisReverse Osmosis

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Reverse OsmosisReverse Osmosis

•The partially permeable membrane in the diagram normally allows water to pass through easily but not the not the dissolved saltsdissolved salts in the sea water.

•This flow of water is called osmosis.

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Reverse OsmosisReverse Osmosis•When a high pressure (about 26 times more than atmospheric pressure) is applied on sea water, the direction of flow reverses. It means water starts flowing from the sea water side to the fresh water side of the membrane.

•This process is called reverse osmosis, thus allowing fresh water to be obtained from sea water.