1Isomers
Same molecular formula but different structural formula
2Order of crude oil fractions
Refinery gases
Gasoline
Kerosene
Diesel
Fuel Oil
Bitumen
3How is crude oil seperated into different fractions?
The oil is heated at a very high temperature until most of it has turned into gas and these gases enter a fractionating column
In the column there is a temperature gradient and when the substances that make up crude oil reach a part of the column where the temperature is lower than their boiling point, they condense
Longer hydrocarbons have high boiling points so shorter hydrocarbons have lower boiling points
4Refinery gases
Used in domestic heating and cooking
5Gasoline (petrol)
Used as fuel in cars
6Kerosene
Used as aeroplane fuel
7Diesel
Used as fuel in some cars and larger vehicles (such as trains)
8Fuel oil
Used as a fuel in large ships and some power stations
9Bitumen
Used to surface roads
10Conditions for cracking
600-700 degrees C
silica or alumina used as a catalyst
11Alkanes
Saturated hydrocarbons
Chlorine and bromine react with alkanes in the presence of UV light (substitution reaction)
methane + bromine -> bromomethane + hydrogen bromide
12Alkenes
Unsaturated hydrocarbons beacuse they contain a double C=C bond
Halogens react with alkenes to make haloalkanes (addition reaction)
bromine + ethene -> dibromoethane
Used to test for alkenes as when you shake them with orange bromine water, the solution goes colourless
13Oxidation of alcohols
Forms carboxylic acids (ethanol -> ethanoic acid)
Needs an oxidising agent of potassium dichromate (VI) in dilute sulfuric acid
14Production of ethanol (from crude oil)
ethene reacted with steam
addition reaction
needs a temperature of 300 degrees and a pressure of 60-70 atm
phosphoric acid used as a catalyst
cheap process but crude oil is a non-renewable resource
15Production of ethanol (fermentation)
Sugar is converted into ethanol using yeast (which is the catalyst)
needs a temperature of 30 degrees
ethanol produced is not very pure but all the raw materials are renewable resources
16Addition polymers
made from unsaturated monomers
most are inert (as the carbon-carbon bonds in the polymer chain are very strong and are not easily broken)
takes a really long time for them to biodegrade
17Condensation polymers
biodegradable so will decompose and do not stay in landfill for a long time