mixtures

mixtures

1. physical methods

   • filltration
     • Mixtures of insouble solid and liquids
       • The filter paper has tiny holes which allow the particles to pass through .The solid particles however are large and cannot pass through the holes and are therefore trapped by the filter paper as residue
         • to get sand from a sand and salt mixture
     • Evaporation
       • mixtures of soluble solids dissolved in liquids
         • The solution is heated until all the water has dried up,leaving the salt behind. note;This method can be only used for heat resistant compounds .
           • to get pure salt crystals from salt solution.
       • magnetic attraction
         • magnetic from non_magnetic metals .non magnetic metals :gold,almunium and lead
           • place magnet close to mixture :magnet will attract only the magnetic substances
             • use of strong magnet to remove iron from scrap metal
   • chromatography
     • Very small amount os substance into its components
       • Draw a pencil line about 5 cm from the bottom of a filter paper .dot the sample ,and known substances (for comparison )with a capillary tube .Hold the filter paper carefully in the solvent
         • plugment from ink. Drugs urine sample
   • simple distilation
     • used to obtain the pure solvent frpm a solution
       • it is also used to purify solids .the solid is dissolved in which is then heated to evaporate most of the solvent (Saturated).ON cooling,the dissolved solids appeacrystals.the impurities remain dissolved in the solutionrs as pure
         • to get water from seawater