Mapa mental

CRACKING

SJ_ Inglês

Mind map: cracking in chemistry

Conteúdo do mapa

CRACKING

Smaller molecules are made from larger molecules
Saturated molecule changes to a smaller unsaturated molecule and a saturated molecule
- Saturated - all single bonds
Heat is used to vapourise the molecule
- Vapourise - change a liquid to a gas by heating
- Vapours pass over a hot catalyst
  - Catalyst - a chemical which makes a reaction go faster
Can be used as a way of making FUELS and POLYMERS
Makes alkenes
- Ethene is an alkene
  - Used to make
    - Ethanol
      - Fermentation is another way to make ethanol
        Sugar--> Carbon dioxide + Ethanol
        Sugar is RENEWABLE
        Yeast is needed for this reaction
      - Ethene + Steam --> Ethanol
        HYDRATION
    - Polymers e.g. poly(ethene)
      - New packaging materials
      - Waterproof coating for fabrics
      - Polymerisation
        Small to large
      - Monomers change to polymers
      - Dental polymers
      - Shape memory polymers
      - Not biodegradable
        Causes problems at landfill sites
- Unsaturated molecules
  - Carbon to carbon double bond
  - C=C
  - Use bromine water as a test
    - Orange to colourless would be seen
- CnH2n
THERMAL DECOMPOSITION