• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

'Petroleum.'Crude oil is a mixture of different hydrocarbons and can be broken down into separate fractions by a process called fractional distillation.

Extracts from this document...


'Petroleum.' Petroleum is also known as crude oil. Petroleum naturally seeps to the Earth's surface along fault lines and cracks in rocks, where it gathers in pools as tar, asphalt or bitumen. From this property it gets its name: the Latin petra, meaning 'rock' and oleum, meaning 'oil', 'rock oil'. Crude oil deposits are found all over the world. Petroleum in a solid form is called asphalt. In liquid form petroleum is called crude oil and in a gaseous form is called natural gas. Petroleum is a mixture of organic compounds containing just two elements: carbon and hydrogen and is the most important natural source of fuel, it is also the source of the raw materials used to make detergents, plastics, paints, anti-freeze, synthetic rubber and medicines. Crude oil is a mixture of different hydrocarbons and can be broken down into separate fractions by a process called fractional distillation. The majority of compounds in crude oil are straight alkanes, but the mixture also contains cycloalkanes and arenas. ...read more.


o Petrol (gasoline) - used for petrol. o Naphtha - used for petrochemicals. o Kerosine (paraffin) - used for jet fuel and petrochemicals. o Gas oil (diesel) - used for central heating fuel and petrochemicals. o Mineral oil (lubricating oil) - used for lubricating oil and petrochemicals. o Fuel oil - used for fuel for ships and power stations. o Wax, grease - used for candles, grease for bearings and polish. o Bitumen - used for roofing and road surfacing. The most useful oil fractions tend to contain the shorter chain hydrocarbons. Petrol is very useful; its chain length can be from C6 to C10. To meet the demand for petrol, larger chains need to be broken down into smaller chains. A process called cracking does this. Cracking is the chemical splitting of long chain alkanes into shorter chain hydrocarbons. Cracking involves a free radical reaction in which carbon-carbon and carbon-hydrogen bonds are broken. ...read more.


Long chained alkane molecules fit into the pores and when this mixture is exposed to a slight pressure and temperature of about 450?C, cracking occurs. Catalytic cracking is a lot cheaper and produces more branched chain molecules than thermal cracking. Branched hydrocarbons burn more easily and so are more useful as fuels. This is the main method of producing petrol. Many fractions obtained from crude oil are used as fuels because they react exothermically when they burn in oxygen. When we use petrol in cars, kerosene in aircraft, fuel oil, heating oil, diesel and natural gas, we use the exothermic energy produced. But burning hydrocarbons also releases carbon dioxide, a greenhouse gas. Impurities present in crude oil can cause environmental problems, for example: crude oil contains sulphur, which after fractional distillation can be found in the petrol fraction. So when the petrol burns, sulphur also reacts with oxygen to form sulphur dioxide, which is released into the atmosphere with the exhaust gases. Sulphur dioxide reacts with water and oxygen in the atmosphere to form sulphuric acid, which can cause acid rain. Charlotte Nellist Chemistry Essay Page 1 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Organic Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Organic Chemistry essays

  1. Marked by a teacher

    Viscosity of Alkanes

    3 star(s)

    Alkane Time in seconds Average Time Average Speed (cm/s)* Test 1 Test 2 Test 3 Test 4 Test 5 Pentane 2.3 1.68 0.81 3.04 2.01 1.968 3.81 Hexane 1.98 1.39 3.18 2.92 3.28 2.54 2.95 Octane 6.6 2.28 3.22 1.38 3.45 4.766 1.57 Decane 2.98 15.42 7.92 14.75 8.64 9.942

  2. Marked by a teacher

    Hydrocarbons and the importance of oil as a power source.

    3 star(s)

    The world's commercial energy supplied by oil is around 40%. This is a big amount as we get 40% of our needs only by using oil. Oil is a very useful source of energy, but one problem is that it is a non-renewable source of energy as one day we

  1. This is a mini-project on fuel - topics include petrol and fossil fuels.

    tree spices in forests or between rows of crops to provide a regular supply of firewood. Many tractors are being converted to be run on sunflower oil instead of diesel. Crops rich in starch and sugar can ferment to produce alcohol, which is added to petrol in many countries, notably Brazil to form what is known as 'gasohol'.

  2. The Energy Content Of Different Fuels

    Energy used & produced to = mass of water X S.H.C X Temp rise heat the water Energy = 25 X 4.2 X 71 = 7455 joules 5. Energy produced per mole = energy produced to heat the water No.

  1. Salters Open Book 2008 Fission and Fusion

    and this energy reaches earth as heat and light energy. As stars evolve, most of the hydrogen gets used up and new fusion reactions begin. Now, the helium nuclei react to form from Beryllium --> Carbon --> Oxygen --> Neon --> Magnesium.

  2. Guide To Hendon Central

    If you want a more �Indian vibe� however, there is a place near the video shop called �Lahore Kebab�. There is also a Tesco shopping centre nearby. Overall Hendon is not the place for tourists, unless you�re that army guy and decide you love the RAF museum so decide to move here permanent!

  1. GCSE Chemistry Revision Notes - everything!

    They have oxides that react with water to produce soluble alkaline hydroxides. They have white compounds that dissolve to produce colourless solutions. To stop them reacting with oxygen or water vapour in the air, lithium, sodium and potassium are stored under oil.

  2. Notes on crude oil and its by-products.

    The acid rain produces many problems. Acid rain can reduce the pH of natural water bodies from between 6.5 and 8.5 to below 4, which will kill fish and other aquatic life. The water is then too acidic to support life. Acid rain also leaches important nutrients from the soil and destroys plants.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work