separation techniques

• Distillation is a method of separation that utilizes the differences in boiling points of substances to separate a mixture into its components.
• Chromatography is used to separate mixtures into their individual components.
• in a mixture of bigger and smaller particles,we can use a sieve of the right pore size to separate the components
• solids that dissolve in the solvents are called solutes
• liquids that dissolve solids are known as solvents
• filtration uses a beaker, filter paper, filter funnel and a conical flask
• the filtrate passes through the filter paper and collects in the conical flask below
• Evaporation to dryness: The process of removing water from a liquid by evaporation. A substance with a lower boiling point will evaporate first, leaving the other substance behind.
• Evaporation to dryness contains evaporating dish, wire mesh, bunsen burner and tripod stand
• The mixture is heated until it reaches its boiling point then cooled slowly so that the solute comes out of solution and forms crystals
• Crystallisation is used to optain a pure solid from a saturated solution
• crystillisation: heat the solution to evaporate most of the liquids until the solution is saturated. Let the solution cool gradually until crystals form and then pour the solution through a funnel lined with filter paper to collect the solid crystals. the crystals are then washed with cold distilled water to remove impurities and dried with filter paper
• simple distillation is used to separate a pure solvent from a solution
• Simple distillation contains distillation flask,boiling chips,thermometer,boiling flask,condesor,conical flask,bunsen burner,tripod stand and a wire mesh(gauze)
• Simple distillation (sea water): Heat up the solution of sea water to 100c so that the water boils and the vapour rises and enters the condensor. the water vapour cools in the condenser and condense back to iquid water so pure water is collected in the conical flask as distillate. as the water vaporise, a solid residue of salt remains in the flask.
• the "water jacket" in the condensor has cold water running through it, entering from the bottom
• paper chromotography is used to separate a mixture of substances which have different solubilities
• paper chromotography contains filter paper, beaker,dye,pencil baseline, solvent(water or ethanol)
• do not submerge the filter paper into the solvent and use a pencil for the baseline and not a pen because the pen's ink will affect the dye/ink they use
• rf value = retardation factor. the ratio of the distance travelled by the substance to the distance travelled by the solvent.
• the further the dye went, the more soluble the dye is
• fractional distillation: its like simple distillation but there are glass beads and it can help take out different liquids if theres more than 2 substance in the solution which has different boiling temperature
• A pure substance has a specific melting and/or boiling point under fixed condition. if there are more impurities added, the melting and boiling point will fluctuate