Organic chemistry

• What formula do alkanes have?

  CnH 2n+2
• What does a saturated compound mean?

  each carbon atom forms 4 single covalent bonds
• What are the formulas for the following alkanes?

  Methane: CH4

  Ethane: C2H6

  Propane: C3H8

  Butane: C4H10
• How do the properties of alkanes change?

  • shorter the chain - more runny hydrocarbon is

  • short carbon chains are more volatile (easily evaporated)

  • shorter chains are more flammible
• What is the equation for combustion?

  hydrocarbon + oxygen -> carbon dioxide + water
• What is the general formula for alkenes?

  CnH 2n
• How are alkenes different to alkanes?

  form double carbon bonds
• What are the formulas for the following akenes?

  Ethene: C2H4

  Propene: C3H6

  Butene: C4H8

  Pentene: C5H10
• What is the equation for incomplete combustion (not enough oxygen)?

  alkene + oxygen -> carbon + carbon monoxide + carbon dioxide + water
• How do alkenes react via additional reactions?

  double carbon bond will open up to single bond and new atom is added to each carbon
• What is the addition of hydrogen to an alkene called?

  hydrogenation
• How do alkenes react to make alcohols?

  ethene reacts with steam and passed over catalyst
• What is made when bromine and ethene react?

  dibromoethane
• How do you test for alkenes?

  add bromine water and it will go colourless, if alkane it will stay bright orange
• What are additional polymers made from?

  unsaturated monomers (alkenes)
• What is additional polymerisation?

  the opening of the unsaturated monomers (alkenes) double bonds and joining them together to make polymer chains
• What is the general formula for alcohols?

  CnH 2n+1 OH
• What are the formulas for the following alcohols?

  Methanal: CH3OH

  Ethanal: C2H5O5

  Propanol: C3H7OH

  Butanol: C4H9OH
• What are alcohols used for?

  • solvents as they dissolve things water can't

  • fuels as they are flammable
• Where is ethanol found?

  alcoholic drinks
• What is the equation for fermentation?

  sugar -> ethanol + carbon dioxide
• What are the formulas for the following carboxylic acids?

  Methanoic acid: HCOOH

  Ethanoic acid: CH3COOH

  Propanoic acid: C2H5COOH

  Butanoic acid: C3H7COOH
• How do carbooxylic acid react?

  • react with carbonates to produce salt, water and carbon dioxide

  • salts formed end in -anoate (methanoic acid - methanoate)

  • methanoic acid + sodium carbonate -> sodium methanoate + water + carbon dioxide

  • can dissolve in water - ionise and release H+ ions but do not ionise fully - form weak acids
• What is the reaction for an ester?

  alcohol + carboxylic acid (acid catalyst) -> ester + water
• What is condensation polymerisation?

  • involves monomers which contain different functional groups

  • monomers react and from bonds between and make polymer chains

  • for each new bond that froms, small molecule (e.g. water) is lost

  • boxes represent carbon chain - in between boxes are the functional groups (normally ester -COO)
• What are the natural occuring polymers?

  • amino acids

  • proteins

  • DNA molecules

  • simple sugars
• How is an amino acid a polymer?

  • contains two different functional groups - basic amino group and an acidic carboxyl group

  • can form polymers called polypeptides via condensation polymerisation
• How are proteins polymers?

  are one or more long-chains of polypeptides
• How are DNA molecules polymers?

  • made of two polymer chains of monomers called nucleocides

  • nucleocides contain bases

  • bases on each polymer chain pait up with each other to from cross links
• How are sugars polymers?

  • sugar contain carbon, oxygen and hydrogen

  • react through polymerisation to form larger carbohydrates polymers
• What is crude oil?

  a fossil fuel made from remains of plants and animals, mainly plankton, due to high pressure and temperatures the remains turned into crude oil
• What is crude oil made from?

  lots of different hydrocarbons most are alkanes
• How does fractional distillation work?

  • oil is heated until most of its a gas, gases then enter the fractionating column

  • column has a temperature gradient

  • the longer the hydrocarbon the higher the boiling point - condense back into liquids and drain out early on
• What products are made from fractional distillation at different temperatures?

  hottest

  • bitumen

  • heavy fuel oil

  • diesel oil

  • kerosene

  • petrol

  • LPG
• What is cracking?


  splitting of long-chain hydrocarbons
• Why do we split long-chain hydocarbons?

  • short-chain hydrocarbons are fammable making good fuels and are high in demand

  • long-chain hydrocarbons are gloopy and make tar

  • makes alkenes - starting material when making compound and make up polymers
• What are the two types of cracking?

  • catalytic

  • steam
• What kind of catalyst is use during cracking after the long-chains are vapourised?


  aluminium oxide