MEPX
Chapter 7 of 10All chapters
  1. 1Atoms
  2. 2The periodic table
  3. 3Bonding
  4. 4Reactions
  5. 5Acids and bases
  6. 6States of matter
  7. 7Mixtures and separation
  8. 8Organic chemistry
  9. 9Chemistry around you
  10. 10Working safely

Chapter 7 of 10

Mixtures and separation

Physically combined, physically separable.

Not compounds

A mixture keeps its components chemically unchanged, so it can be separated physically. A compound has new properties entirely: sodium and chlorine are dangerous, salt is dinner.

  • Filtration, distillation, evaporation and chromatography exploit different physical differences.
  • Solubility depends on temperature, which is why hot water dissolves more sugar.

Concentration

Concentration says how much solute sits in a given amount of solvent. Getting it wrong is the difference between a medicine and a poison, which is most of pharmacology.