Organic Chemistry

• what is crude oil

  a finite resource found in rocks
• where is crude oil found

  in the remains of an ancient biomass consisting of plankton buried in mud
• what is the structure of crude oil

  a mixture of lots of compounds

  • the chemical properties of each substance are unchanged
  • most compounds consist of molecules of only hydrocarbons that are saturated alkanes
• how are the compounds of crude oil separated

  physical methods

  • such as distillation
• what is the general formula for alkanes

  Cn H2n+2
• what are saturated hydrocarbons

  alkanes
• what are the first 4 alkanes

  Methane

  Ethane

  Propane

  Butane

  (Men Eat Poopy Buts)
• what are the steps of fractional distillation

  • oil is heated in the fractioning column + evaporated + condenses at different temperatures
  • hydrocarbons in crude oil are separated into fractions which contain molecules with similar numbers of C atoms
  • heated crude oil is piped in at the bottom + the vaporized oil evaporates and rises up the column
  • fractions are constantly tapped off at the different levels where they condense
  • fractions can be processed to produce fuels
• what size of hydrocarbon molecules are more viscous

  longer molecules
• what size of hydrocarbon molecules are more flammable

  shorter molecules
• what size of hydrocarbon molecules vaporise at lower temperatures

  shorter molecules
• what do hydrocarbons produce when burnt

  energy

  hydrocarbon -> CO2 + H2O

  • H + C are oxidised here
• why are hydrocarbons cracked

  to produce smaller + more useful molecules
• how are hydrocarbons cracked

  heating the hydrocarbons to vaporise them

  • catalytic cracking -> passing them over a hot catalyst
  • steam cracking -> mixing them with steam + heating to high temps so thermal decomposition occurs
• what are the products of cracking

  alkanes + alkenes
• which type of hydrocarbon have a double carbon bond

  alkenes
• what is the general formula for alkenes

  Cn H2n
• what are unsaturated hydrocarbons

  alkenes
• what are the first 4 alkenes

  Ethene

  Propene

  Butane

  Pentene

  (Even Princes Break Princesses)
• how do different hydrocarbons react with bromine water

  alkenes

  • turn it from orange -> colourless

  alkenes

  • doesnt react
  • not as reactive as alkenes double bond
• what do you need to remember about cracking equations

  • needs to be same no. of C and H on either equation sides
  • moves from bigger molecule -> 2 smaller molecules
• why are alkenes unsaturated

  they contain 2 fewer H atoms than alkanes with same number of C atoms
• what is the functional groups of alkenes

  C = C
• how do alkenes react with oxygen in combustion reactions

  • burn un air with smoky flames
  • due to incomplete combustion -> carbon or carbon monoxide is former
• how do alkenes react with hydrogen + water + halogen

  • addition of atoms across the double C bond
  • double bond becomes a regular single bond
  • compounds split into 2 groups -> the two groups add to the two Cs in the different C=C bond (each group can be added to either C)
  • H2 -> 2 Hs
  • H2O -> H + OH
  • Br2 -> 2 Brs
• what is the functional group of alcohols

  -OH
• what are the first 4 members of the alcohol group

  Methanol

  Ethanol

  Propanol

  Butanol

  (Men Eat Poopy Buts)
• what is the general formula of alcohols

  Cn H2n+1
• how do alcohols react with air

  burn in air

  • produces CO2 + H2O
• how do alcohols react with water

  dissolve

  • form a neutral solution (pH 7)
• how do alcohols react with sodium

  • produces hydrogen + salt
• how do alcohols react with oxidising agents

  carboxylic acids
• what can alcohols be used as

  fuels

  methanol -> chemical food stock + biodiesel maker

  ethanol -> in alcoholic drinks + solvent
• how is ethanol produces

  sugar -> ethanol + CO2

  • 35 degrees
  • anaerobic
  • yeast enzyme catalyst
• what is the functional group of carboxylic acid

  -COOH
• what are the first 4 members of the carboxylic acid group


  Methanolic acid

  Ethanoic acid

  Propanoic acid

  Butanoic acid

  (Men Eat Poopy Buts)
• what is the general formula for carboxylic acid

  Cn H2n+1 COOH
• how do carboxylic acids react with water

  produce acidic solutions

  • pH less than 7
• how do carboxylic acids react with metal carbonates

  produces CO2 + H2O + a salt

  • turns limewater cloudy
• how do carboxylic acids react with alcohols

  produces esters (ie. ethyl ethanoate)

  • in the presence of an acid catalyst