c1 revision

Topics: Oxygen, Carbon dioxide, Carbon Pages: 7 (3330 words) Published: October 23, 2014

OCR gateway Core C1 revision notes
Anything written in purple is for higher tier
Exam tips are in red
Fossil Fuels
3 types
Coal (made from dead plants that lived millions of years ago) Crude oil (made from dead sea creatures that lived millions of years ago) Natural gas (made from dead sea creatures that lived millions of years ago) Key words to learn

Non-renewable- fossil fuels are said to be this as we are using them up faster than they can be made Finite- these will run out if we continue using them
Crude oil
This fossil fuel is made up of a mixture of hydrocarbons. Hydrocarbons are compounds that contain hydrogen and oxygen atoms only a) b)
In the exam you may be asked to identify hydrocarbons from their structure. You can see that a) is not a hydrocarbon as it contains oxygen as well Crude oil on its own is not useful but the hydrocarbons it contains on their own are useful and so they need to be separated. They are separated by a process called fractional distillation and this happens in a fractionating column

You might have a diagram like the one above and you have to label the fractions in the order they come off the column and so learn them. You also need to learn what the fractions are used for The fractionating column is heated at the bottom so the bottom is much cooler than the top of the column. The crude oil is piped into the fractionating column and heated. In the exam you could be asked by what property difference are the different hydrocarbons (called fractions) separated by and the answer is Boiling Point Small hydrocarbons have low boiling points so when the crude oil is heated, they travel to the top of the column and leave as a gas (LPG) Hydrocarbons with the highest boiling points stay as a liquid and leave at the bottom of the column (bitumen). In the exam you could be ask to label where on the column bitumen leaves, and you would put an X on the tube at the bottom of the column) Other fractions turn into a gas at the bottom of the column, they rise up the column and where they cool, turn into a liquid, and are piped off the column Hydrocarbons molecules are held together by intermolecular forces. The larger the hydrocarbon, the more intermolecular forces that are holding the molecules of the hydrocarbon together. This means a higher temperature is needed to separate the molecules and turn that hydrocarbon into a gas. Drilling for oil

Oil was formed millions of years ago from sea creatures and so is trap under layers of impermeable rock (the oil cannot get through). Therefore oil wells drill through the rock to get at the oil. Problems with oil- it is transported in tankers on the sea and sometimes the tankers get damaged and the oil leaks out causes environmental problems
The oil ruins beaches and birds get covered in oil and cannot fly. They cannot feed and die. Detergents are used to try and break the oil up but this also damages wildlife. Political problems that can be caused by crude oil- oil mainly produced by countries in the Middle East and consumed by the most by USA and Europe. The Middle East could decide to reduce supplies or put up prices anytime. Cracking

Some fractions and more useful and so more in demand than others (e.g. petrol is more demand than bitumen). In the exam you could get a bar chart or a table for you to identify which fractions are in more/less demand than others

Cracking is a process by which larger, less useful hydrocarbons are cracked into smaller more useful ones to match demand. Cracking involves heating larger oil fractions and passing them over a catalyst Octane hexane + etheneC8H18 C6H14 + C2H4 This means that cracking cracks a large alkane into a smaller alkane and an alkene In the exam you could be asked what cracking is, what conditions are needed and what is produced. Alternatively you could have the label the diagram below....
Continue Reading

Please join StudyMode to read the full document

You May Also Find These Documents Helpful

  • Revision Techniques Essay
  • English Revision Paper
  • C1 Revision Notes Essay
  • C1 C2 M1 Revision Essay
  • Essay about Revision
  • Revision Essay
  • Revision Essay
  • Revision Research Paper

Become a StudyMode Member

Sign Up - It's Free