crude oil

• What is crude oil classified as?

  Finite (non-renewable) fossil fuel
• How is crude oil formed?

  From remains of ancient marine organisms
• What is the main composition of crude oil?

  Mixture of hydrocarbons, mainly alkanes
• How is crude oil extracted?

  Extracted from the Earth’s crust
• What process is used to refine crude oil?

  Fractional distillation
• What are the key points about crude oil?

  • Mixture of hydrocarbons
  • Formed over millions of years
  • Finite resource (will run out)
• What are hydrocarbons made of?

  Hydrogen (H) and carbon (C) atoms
• Where are hydrocarbons found?

  In crude oil and used as fuels
• What are the types of hydrocarbons in crude oil?

  • Alkanes (saturated hydrocarbons)
  • Alkenes (unsaturated hydrocarbons)
• What is the general formula for alkanes?

  $C_nH_{2n+2}$
• What type of bonds do alkanes have?

  Only single bonds (C–C)
• What is the general formula for alkenes?

  $C_nH_{2n}$
• What is fractional distillation?

  A separation process based on boiling points
• What equipment is used in fractional distillation?

  A fractionating column
• What happens to crude oil during fractional distillation?

  It is heated and separated into fractions
• At what temperature is crude oil heated for distillation?

  Around 350°C
• What is the temperature gradient in a fractionating column?

  Hot at the bottom, cooler at the top
• Why do different hydrocarbons condense at different levels?

  Based on their boiling points
• What are the fractions obtained from crude oil and their uses?

  • Refinery gases: Bottled gas, LPG
  • Gasoline (petrol): Car fuel
  • Naphtha: Chemical industry
  • Kerosene: Jet fuel
  • Diesel: Lorries, trains
  • Fuel oil: Ships, power stations
  • Bitumen: Roads, roofing
• What is the trend in fractions regarding boiling points and flammability?

  Smaller molecules = lower boiling point
• Why is cracking needed for hydrocarbons?

  To break long-chain hydrocarbons into useful fuels
• What are the types of cracking?

  • Thermal cracking: High temperature & pressure
  • Catalytic cracking: Uses a catalyst
• What is the temperature range for thermal cracking?

  ~700-1000°C
• What does catalytic cracking use?

  A zeolite catalyst
• What is complete combustion?

  Burning hydrocarbons completely in oxygen
• What are the products of complete combustion?

  Carbon dioxide and water
• What is incomplete combustion?

  Burning hydrocarbons with limited oxygen
• Why is complete combustion good for the environment?

  No harmful gases are produced
• What are the products of incomplete combustion?

  Carbon monoxide and soot
• What are the dangers of incomplete combustion?

  Produces toxic carbon monoxide and soot
• What pollutants are produced from burning fossil fuels?

  • Carbon dioxide (CO₂): Global warming
  • Carbon monoxide (CO): Toxic gas
  • Soot (particulates): Respiratory issues
  • Sulfur dioxide (SO₂): Acid rain
  • Nitrogen oxides (NOx): Acid rain & smog
• How does carbon dioxide affect the environment?

  Contributes to global warming
• What is the effect of carbon monoxide?

  Toxic gas that affects oxygen transport
• What health issues does soot cause?

  Respiratory issues and global dimming
• What causes acid rain?

  Sulfur dioxide in fuels
• What causes smog?

  Nitrogen oxides from car engines
• How can pollution from fossil fuels be reduced?

  • Catalytic converters remove CO & NOx
  • Low-sulfur fuels reduce SO₂ emissions
  • Renewable energy reduces fossil fuel dependence
• What are the advantages and disadvantages of alternative fuels?

  Advantages:

  • Renewable, carbon-neutral (biofuels)
  • No CO₂ emissions (hydrogen fuel)
  • No exhaust gases (electric cars)

  
  

  Disadvantages:

  • Uses farmland (biofuels)
  • Hard to store (hydrogen fuel)
  • Batteries require mining (electric cars)
• What are the key points summarized about crude oil?

  • Mixture of hydrocarbons, finite fossil fuel
  • Fractional distillation separates hydrocarbons by boiling point
  • Smaller molecules = better fuels, larger molecules = sticky
  • Cracking breaks long hydrocarbons into smaller ones
  • Combustion: Complete (CO₂ + H₂O) vs. Incomplete (CO + soot)
  • Pollution: CO₂ = climate change, CO = toxic, SO₂ = acid rain
  • Alternative fuels: Biofuels, hydrogen, electric cars