Presentation on theme: "Separation Techniques"— Presentation transcript:
1Separation Techniques Text by Mrs TeoVideo clips taken from school video repository
2The Different Separation Techniques are as follows: Magnetic attractionFiltrationEvaporationCrystallisationDistillationChromatographyNote: The physical method used will depend on the nature of the constituents.
3Magnetic Attractionused to separate magnetic materials, e.g. iron, steel, nickel, cobalt from non-magnetic ones in a mixturee.g. separating iron filings from sulphur powder.
4Applications of Magnetic Attraction Electromagnets are used to remove steel and iron scrap at the junk-yard.2. In hospitals, magnets are often used to remove iron splinters from a patient’s eyes.
5Using a Separating Funnel can be used to separate twoimmiscible liquids, such as oiland water.
6Filtration used to separate an insoluble solid from (i) a liquid in a solid-liquid mixturee.g. sand from a mixture of sand and water or(ii) a soluble solide.g. calcium carbonate from mixture of itand copper(II) sulphate.
7Filtration insoluble solid that remains on the filter paper - residue. liquid that passes through- filtrate.
8Applications of Filtration hair in our nostrilstrap the dust particles that we breathe in and allow only clean air to pass throughair filters in air conditionersremove solid impurities from airoil and air filters in carsremove solid impurities found in engine oil and air
9Evaporation to dryness used to separate a dissolved solid that does not decompose on heating from a solution,e.g. common salt from a salt solution.
10Procedure of Evaporating a Solution 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.
11Applications of Evaporation drying wet clothesdrying hair with a hair-dryerobtaining common salt from the sea
12Crystallisationprocess to obtain a solid that decomposes on heating from its solution.e.g. sugar from sugar solution and copper(II) sulphate crystals from copper(II) sulphate solution
13Distillationprocess used to separate a liquid (solvent) from a solid-liquid solution or liquid-liquid solution.e.g. pure water can be distilled from soft drinks
15Fractional Distillation process can be used to separate miscible liquids with different boiling pointsliquid with lower boiling point will vaporize firste.g. to separate alcohol and water
16Industrial Applications of Fractional Distillation oil refineries - separating the various components of crude oil or petroleumindustries supplying oxygen to hospitals, shipyards, etc – separating the components of air
20Paper Chromatographyprocess used to separate the different components in a liquid mixture For example it can be used1. to separate the different coloured components that make up black ink2.to detect tiny amounts of drugs or certain other chemicals in urine samples.
21Paper Chromatography1. Apply a small but concentrated spot of the solution on a piece of chromatography paper.2. Suspend the chromatography paper in a beaker or boiling tube of solvent with the spot above the level of the solvent.
22Paper Chromatography3. 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.
23Paper Chromatography3. As the solvent travels up the paper, the mixture is separated into its respective components.A chromatogram of the separated components is obtained.