atomic structure and the periodic table

• what are all the types of separation techniques?

  Fractional distillation, distillation, evaporation, filtration, chromatography, crystallisation
• what is an Rf value?

  Ratio of the distance traveled by a compound to the distance traveled by the solvent front in thin layer chromatography.
• what is the result of paper chromatography?

  a chromatogram
• what is distillation used for ?

  separating out a liquid in a solution.
• what is the problem with distillation?

  can only be used with substances with very different boiling points
• why is fractional distillation more accurate?

  temperature gradient along a long collum, the top is the only part hot cool enough for just the substance you want to collect and no others.
• how are atoms organised in the modern periodic table?

  in order of increasing atomic number, meaning there are repeating patterns of property