Organic

Cracking is the process of taking long chain hydrocarbons which are not very useful to us and breaking them down into smaller, more useful products. For example making petrol (for cars) and ethane (to make polythene).

What would we do if we ran out of petrol?

• Switch to electricity(electric powered cars)
• Bio Mass fuels
• Faeces

In this experiment we set up the equipment and heated up the test tube until the water fron the othet tube was gone and gas was in its place. The ceramic chips / porcelain chips were there to act as a catalyst. The air left the tube first because it was filling the tube so had to go somewhere. The product was a clear gas and smelled strongly. If you set the gas on fire it would burn with a blue flame. 

• Fractional distillation differs from distillation only because it seperates a mixture into a number of different parts, called fractions. 
• A tall column is fitted above the mixture with several condensers coming off at different heights.
• The column is hot at the bottom and cool at the top.
• Substances with high boiling points condense at the bottom and substances with low boiling points condense at the top.
• Like distillation, fractional distillation works because the different substances in the mixture have different boiling points.

•  Alkenes are another family of hyrdocarbons.
• They  all contain a double bond which is shown as two lines between two carbon atoms - they are unsaturated
• The presence of the double bond allows alkenes to react in a way which alkanes cannot. They react with ocygen in the air so could be used as fuels. They can also be used to make ethanol - alcohol and polymers - plastics.
• The generalformula means that the number of hydrogen atoms in an alkene is double the number of carbon atoms. For example, ethane is and CnH2n.
  
• Alkene molecules can be represented by displayed formulae, in which each atom is shown as its symbol (C or H) and the chemical bonds between them by a straight line.
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• Cracking alkenes is taking long hyrdocarbons and making two smaller ones.
  E.g:

• Alkanes are a type of hydrocarbon
• Hydrocarbons are compounds made from carbon and hydrogen atoms joined by covalent bonds.
• A covalent bond is a shared pair of electrons.
• Alkanes do not react with brown bromine water and decolourise.
• Alkanes are saturated (they only have single bonds). 
• Most of the compounds in crude oil are hydrocarbons.

• The number of hydrogen atoms in an alkane is double the number of carbon atoms plus two. Eg: Methane = CH4. Methane = C2H6 
  
  
• Alkane molecules can be represented by displayed formulas in which each atom is shown as its symbol (C or H), and the covalent bonds between them by a straight line.