Separating Substances

Separating Substances

1. Describe paper chromatography

   • Paper Chromatogarphy can be used to seperate mixture of substances. It can be used to identify substances. The most souable a substance is in the solvent,the further it wil travel up the chromatography paper.
   • You can use paper chromatography for identify substances, seperate mixture of substances, purify a substance by seperating it from its impurities,
   • Rf value =DIstance travelled by the sample/Distance travelled by the solvent

2. Describe methods of separation and purification: filtration, crystallisation, distillation, fractional distillation

   • Filtration- Used to seperate a solid from a liquid.E.G- Sand and water
   • Crystallisation- A solute from its sloution. E.g- sugar and water
   • Distillation- A slovent from its sloution.E.G- obtain water from a slat water solution.
   • Fractional distillation- Liquids from each other.Eg- ethanol and water

3. Identify substances and assess their purity from melting point and boiling point information

   • Pure substance- It has a definite and shrp melting and boiling point
   • Impurity- it is a substance have a lower than usual melting point and higher than usual boiling point.

4. Understand the importance of purity in substances in everyday life, e.g. foodstuffs and drugs

   • The purity of a substance also impacts the chemical properties of a substance by reducing the chances of unexpected products being formed if impurities are present within the substance.

5. Suggest suitable purification techniques, given information about the substances involved