seperating techniques

the mixture of different substances where no chemical reaction has occurred

the iron is grey, sulphur is yellow the iron reacts with dilute hydrochloric acid producing hydrogen sulphur doesn’t react with acid the compound of iron sulfide reacts with acids to produce poisonous hydrogen sulfide gas, which smells of eggs

colourless gas that explodes when you put a flame to it

by physical means, like change in temperature or dissolving part of mixture ways that don’t involve any chemical reactions

use a magnet

physical process oxygen condenses into liquid at a higher temperature than hydrogen liquid oxygen and hydrogen gas

pure substances - melt and boil at fixed temperatures mixtures - melt and boil over a range of temperatures presence of impurities lowers the melting point and raises the boiling point

can be used to separate a solid from a liquid substance that is left in filter paper is called residue the liquid that comes through is called filtrate

filter paper funnel beaker

used to separate a solute from a solution seperate sodium chloride from sodium chloride solution solution heated in an evaporation basin to boil off the water until a saturated solution is formed can be tested by dipping a glass rod into the solution and seeing if crystals quickly form on it’s surface bunsen burner is then turned off and the crystals form as the water continues to evaporate and solution cools crystals can nor be removed from mixture using filtration

bunsen burner tripod gauze evaporation basin glass rod

used to separate the components of a solution water boils and condenses back to a liquid by the condenser to a beaker salt remains in flask

conical flask bung gauze bunsen burner condenser beaker

used to separate a mixture of liquids separated by taking advantage of their boiling points both liquids boil but control temperature carefully using thermometer

thermometer fractional column flask gauze bunsen burner condenser beaker

used to separate a variety of mixtures of coloured inks or food colouring used to separate colourless substances like sugars too

• draw a line in pencil across a piece of chromatography paper - do not use pen as its inks will move up the paper with the solvent • place the dye dots on the pencil line and let dry • suspend chromatography paper into beaker that contains solvent that only the bottom bit of paper goes into - important that solvent is below pencil line so inks don’t just dissolve into solvent • put a lid on the breaker so that atmosphere becomes saturated with solvent , and stopping evaporation of the solvent from the paper • when solvent has moved up paper and reached 1cm away from the top remove paper from beaker and draw a line using a pencil to show where solvent got to • leave paper to dry so solvent evaporates

solvent front

chromatogram