8chemical analysis

Cards (20)

  • what is a pure substance
    something that only contains one compound or element throughout
  • how can you test the purity of a substance sample
    measuring its melting and boiling point and comparing it to melting and boiling point of other pure substances, the closer your measured value is to the actual melting or boiling point the purer your sample is
  • what will impurities in your sample do to the melting and boiling point
    increase it
  • what are formulations
    useful mixtures with a precise purpose that are made following a ‘formula’
  • what are paint formulations made out of
    pigment, solvent, binder, additives
  • what is pigment
    gives the colour
  • what is solvent
    used to dissolve other components and alter viscosity
  • what is a binder
    forms a film that holds pigment in place
  • what is the additives
    added to further change the physical and chemical properties
  • why are formulations important in the pharmaceutical industry
    chemists can make sure that drugs are transported to the right part of the body at the correct concentration, that its consumable and has a long shelf life
  • where can formulations be found in everyday life
    cleaning products, fuels, cosmetics, fertilisers, metal alloys, food and drink
  • what is chromatography
    an analytical method used to separate the substance in a mixture
  • what is the mobile phase
    where molecules can move, liquid or gas
  • what is the stationary phase
    where molecules can’t move, solid or really thick liquid
  • what will a pure substance only ever do in chromatography
    form one spot on the paper
  • during chromatography what constantly happens
    the substance moves through the mobile and stationary phase so that an equilibrium is formed
  • what is the stationary phase in chromatography
    the chromatography paper
  • what is the mobile phase chromatography
    the solvent
  • what does the amount of time the molecules spend in each phase depend on
    -how soluble they are
    -how attracted they are to the paper
  • what is the Rf values equation
    distance travelled by substance/distance travelled by solvent