*strategy:devise a process that discriminates between components with different properties.
e.x:high density/low density
separation
-components in a mixture retain their identities
-the more similar the properies, the more difficule it is to separate them.
some Basic Techiques
1.Filtration:(solid and liquid) can remove suspended material from water as long as the pores in the filter paper are smaller than the particles of the suspended substance.
2.Floation:
3.crystallization and Extraction:(solid in liquid)
-precipitation
-solid are them separated by filtration or floating
-saturated solution of a desired solid.
4.Distillation:(liquid in liquid solution)
-lteating a mixture can cause low-boiling components to volatilize
-then collect and condense the volatilized components
5.chromatography:is a method for analyzing complex mixtures (such as ink) by separating them into the chemicals from which they are made. Chromatography is used to separate and identify all sorts of substances in police work. Drugs from narcotics to aspirin can be identified in urine and blood samples, often with the aid of chromatography.
.http://www.yesmag.ca/projects/paper_chroma.html see more information about chromatography.
6.solven extraction:
-mechanical mixture
-use liquid to dissolve one solid but not the other so the desired solid is left behind or dissolved
7.Gravity Separation:
-A centrifuge whirls the test tube around at high speeds forcing the denser materials to the bottom.
Hand Separation
-hand separation(soild and solid)
-A mechanical mixture or heterogeneous mixture can be separated by using a magnet or sieve
Evaporation
-Boil away the liquid and the solid remain
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