C6 - Detective Chemistry

C6 - Detective Chemistry

1. Separation Techniques

   • Mixtures
     • Two or more substances that are not chemically bonded Can be separated through physical means
     • Types Of Filtration
       • Solid - Solid
       • Liquid - Liquid
         • Fractional Distillation
           • 1. Heat solution to lowest boiling point 2. Evaporation occurs and a bit of both gases go up into the fractionating column 3. Glass beads cause temperature gradient, so higher boiling point liquid condenses while other liquid goes up to the condenser and forms in a flask
       • Liquid - Solid
         • Soluble
           • Evaporation
             • Heat the solution in an evaporating dish.  The liquid should evaporate into the air, leaving you with just the solute.
             • Stable and Unstable Solids
               • Stable - Heat will not decompose Unstable - heat will decompose compound into different molecules/atoms
           • Crystallization
             • Heat the solution to saturation/crystallization point - no more solute dissolves in solvent Stop heating at this point, and wait for crystals to form
         • Insoluble
           • Filtration
             • Filter paper, funnel, filtrate and beaker Put filter paper in conical shape and put it over funnel. Put the funnel over the beaker and pour the filtrate into the funnel Solids and liquids seperated
         • Distillation
           • Process
             • Heat up solution to boiling point of solvent Evaporation causes solvent to turn into gas and go up tube into condenser Due to cool water/liquid, solvent cools into liquid and drips into flask or container
           • Reasoning
             • One has a higher boiling point than the other, so it can withstand a higher temperature. Doing this allows the substance with a lower boiling point to be completely chemically separated from the solute, and collected in another flask

2. Tests

   • Cations
   • Anions
   • Gases