crude oil, cracking & burning hydrocarbons

• what is crude oil ?

  molecules which are only made of carbon and hydrogen
• how are the different compounds in crude oil seperated ?

  fractional distillation
• LABEL THE DIFFERENT FRACTIONS

  A) bitumen

  B) fuel oil

  C) diesel

  D) kerosene

  E) gasoline

  F) refinery gases

  G) 350 C

  H) 25 C

  
• what is fuel oil used for ?

  fuel for ships and power stations
• what is diesel used for ?

  fuel for cars, lorries and buses
• what is kerosene used for ?

  aircraft fuel
• what is gasoline used for ?

  fuel for cars
• what is refinery gases used for ?

  domestic heating and cooking
• long hydrocarbons have high boiling points and are viscous while shorter hydrocarbons have lower boiling points and are much thinner and paler in colour.
• the demand in short-chain hydrocarbons like octane which is used in petrol (gasoline) is much higher than for longer-chain hydrocarbons.
• to meet the high demand, long chain hydrocarbons are split into more useful short-chain molecules using cracking
• what is cracking ?

  a form of thermal decomposition, by breaking down molecules into simple molecules by heating them
• what are the 2 catalysts used to be passed over by vaporised hydrocarbons ?

  Alumina and Silica
• In industry, vaporised hydrocarbons are passed over a powdered catalyst at about 600-700 C. Silica or Alumina are used as the catalyst
• what happens when you burn a fuel ?

  it releases energy in the form of heat
• what is burning known as ?

  combustion
• what are the results of incomplete combustion ?

  Carbon monoxide, soot, and water vapor
• what happens if there is not enough oxygen in complete combustion ?

  Incomplete combustion
• what can carbon monoxide do affecting your oxygen ?

  Carbon monoxide binds to hemoglobin in red blood cells, reducing their ability to carry oxygen around the body
• what can a lack of oxygen in the blood supply to the brain lead to ?

  fainting, a coma or death
• what is acid rain caused by ?

  sulfur dioxide and nitrogen oxides
• what may be produced when fractions from crude oil are burnt as fuels ?

  sulfur dioxide and nitrogen oxides
• where does the sulfur dioxide come from when produced ?

  sulfur impurities in the hydrocarbon fuels
• where does the nitrogen oxide come from when produced ?

  when the temperature is high enough for oxygen and nitrogen in the air to react
• what does nitrogen oxide include ?

  nitrogen monoxide and nitrogen dioxide
• what happens when sulfur dioxide and nitrogen oxides mix with water vapour in clouds ?

  they form dilute sulfuric acid and nitric acid
• what does acid rain affect ?

  it causes lakes to become so acidic any plants and animals die as a result