Organic Chemistry

• What is organic chemistry primarily concerned with?

  Compounds that contain carbon
• What are hydrocarbons?

  They are the simplest organic compounds
• What elements do hydrocarbons contain?

  Hydrogen and carbon atoms
• Why is CH₃COOH not a hydrocarbon?

  It contains oxygen atoms
• What is the general formula for alkanes?

  CₙH₂ₙ₊₂
• What are the characteristics of alkanes?

  • Simplest type of hydrocarbon
  • Homologous series
  • Saturated compounds
  • First four alkanes: methane, ethane, propane, butane
• What are the first four alkanes?

  Methane, ethane, propane, butane
• How do hydrocarbon properties change with chain length?

  They change as the carbon chain lengthens
• What happens to viscosity as the carbon chain gets shorter?

  It becomes less viscous
• What is the volatility of shorter carbon chain hydrocarbons?

  They have lower boiling points
• How does flammability change with carbon chain length?

  Shorter chains are more flammable
• Why are short chain hydrocarbons used as bottled gases?

  They have lower boiling points
• What occurs during complete combustion of hydrocarbons?

  It releases energy, CO₂, and water
• What are the waste products of complete combustion?

  Carbon dioxide and water vapour
• What happens to carbon and hydrogen during combustion?

  They are oxidised
• Why are hydrocarbons used as fuels?

  Due to energy released during combustion
• What is the balanced equation for the complete combustion of methane?

  CH₄ + 2O₂ → CO₂ + 2H₂O
• How do you balance the combustion equation for methane?

  Balance carbon, then hydrogen, then oxygen
• What is the process of complete combustion of ethane (C₂H₆)?

  1. Ethane reacts with oxygen
  2. Produces carbon dioxide and water
  3. Releases energy
  4. Balanced equation: C₂H₆ + 7/2 O₂ → 2CO₂ + 3H₂O
• What is crude oil primarily used for?

  Making fuels and other useful products
• Why can't crude oil be used directly in cars?

  It needs to be separated into hydrocarbons
• What is crude oil classified as?

  A fossil fuel
• How is crude oil formed?

  From remains of plants and animals buried in mud
• What conditions are necessary for the formation of crude oil?

  High temperatures and pressure over millions of years
• Why are fossil fuels considered non-renewable?

  They take millions of years to form
• What are hydrocarbons?

  Molecules containing only hydrogen and carbon
• What is the purpose of fractional distillation?

  To separate different hydrocarbon fractions
• What happens to crude oil during fractional distillation?

  It is heated until most turns into gas
• What is a temperature gradient in a fractionating column?

  It is hot at the bottom and cooler at the top
• How do boiling points affect the separation of hydrocarbons?

  Longer hydrocarbons have higher boiling points
• Where do longer hydrocarbons condense in the fractionating column?

  Near the bottom of the column
• What is the result of fractional distillation of crude oil?

  Different fractions with similar carbon atoms
• What are the main fractions obtained from crude oil through fractional distillation?

  • LPG (Liquefied Petroleum Gas)
  • Petrol
  • Kerosene
  • Diesel oil
  • Heavy fuel oil
  • Bitumen
• What is the approximate number of carbon atoms in LPG?

  ~3
• What is the approximate number of carbon atoms in petrol?

  ~8
• What is the approximate number of carbon atoms in kerosene?

  ~15
• What is the approximate number of carbon atoms in diesel oil?

  ~20
• What is the approximate number of carbon atoms in heavy fuel oil?

  ~40
• What is bitumen used for?

  Heating oil, fuel oil, or lubricating oil
• How much petrol is there in crude oil?

  Just a fraction