Crude oil, hydrocarbons and cracking

• Cracking refers to the process of breaking down large hydrocarbons into smaller ones by heating them in a presence of a catalyst.
• The products of cracking include?

  Alkanes and Alkenes
• Hexane

  C6H14
• Butane

  C4H10
• Ethene

  C2H4
• Crude oil can be separated into fractions such as gasoline, kerosene, diesel fuel, heating oil, lubricating oil, waxes, and asphalt.
• The larger alkanes are heated around 650 degrees and their vapours are passed over a hot catalyst containing aluminium oxide. This causes covalent bonds to break and reform.
• Give two reasons why cracking is important:

  1. It helps to match the supply of fractions with the demand for them.
  2. It produces alkenes, which are useful feedstock for the petrochemical industry.
• Cracking increases the yield of useful products from crude oil.
• Cracking produces more useful fuels with lower boiling points than those present in crude oil.
• Cracking allows us to produce fuels with different boiling points (e.g. petrol).
• Alkanes are saturated which means their carbon atoms are only joined by C-C single bonds.
• Alkenes are unsaturated which means they contain at least one C=C double bond.
• Alkanes are more reactive than alkanes. Alkenes can take part in reactions that alkanes can't.
• Hydrocarbons are compounds that contain hydrogen and carbon atoms only.
• Crude oil is a limited resource that is found in the earth's crust.
• Crude oil is the remains of organisms that lived and died millions of years ago.
• Crude oil contains many impurities such as sulfur, nitrogen, oxygen, and metals like nickel and vanadium.
• The formation of crude oil involves the decomposition of dead plants and animals over millions of years under high pressure and temperature conditions.
• Crude oil is a complex mixture of hydrocarbons. The carbon atoms in these molecules are joined together in chains and rings.