Organic Chemistry - A level AQA

• Why is carbon useful?


  Carbon can make 4 covalent bonds, it can form chains with itself (catenation), it can bond to many different elements and is stable
• what are typical properties of organic compounds?


  most are simple molecular therefore have low melting and boiling points due to weak intermolecular forces.
• What are hydrocarbons?


  molecules made up of carbon and hydrogen atoms only
• What is the general formula for alkanes?

  
• What is the general formula for alkenes?

  
• What is the prefix for a molecule containing 1 carbon?

  meth
• What is the prefix for a molecule containing 2 carbons?

  eth
• What is the prefix for a molecule containing 3 carbons?

  prop
• What is the prefix for a molecule containing 4 carbons?

  but
• What is the prefix for a molecule containing 5 carbons?

  pent
• What is isomerism?


  Different substances with the same molecular formula but different structural formulas
• What is structural isomerism?


  different substances with the same molecular formula but with the atoms bonded in different ways
• what is structural isomerism split into?


  chain, positional and functional group
• what is functional group isomerism?


  different substances with the same molecular formula but different functional group
• what is positional isomerism?


  substances with the same molecular formula and functional group but the functional group is found in a different position
• what is chain isomerism?


  isomers in which the carbon chain is ordered in a different way
• what is stereo isomerism?


  different substances with the same molecular formula and bonding, but with different spatial arrangement of atoms
• what is stereo isomerism split into?


  geometric and optical
• what is geometric isomerism?


  different substances with the same molecular formula but where there is a lack of rotation around a carbon double bond. Therefore occurs when you have restriction somewhere in the molecule
• How do you name geometric isomers?


  If the highest priory groups are on the opposite sides of the carbon double bond its (E)-isomerism, but if the two highest priority groups are on the same side its (Z)-isomerism. REMEMBER (Z)-ame side
• What are features of the homologous series?


  Have the same general formula, the length of the carbon chain has little effect of chemical reactivity of functional group, length of the carbon chain can affect physical properties, same functional group.
• What is crude oil?


  mixture of hydrocarbons, non-renewable
• What is the fractional distillation of crude oil?


  Separates crude mixture into more useful products. Vaporize crude oil and pass into a fractionating column. Gases condense at different level, these mixtures are then piped off.
• what are zeolites?


  catalyst used in alkane cracking
• what does poisoned mean in terms of catalysts?


  when a catalyst has impurities which can lead to an inefficency = catalysts poisoning
• what is a side chain with one carbon know as?


  methyl-
• what does saturated mean?


  full amount of bonds, no double or triple bonds
• What are the first 5 alkanes?


  Methane, ethane, propane, butane, pentane
• What is the major use of alkanes?


  combustion
• what is complete combustion and what is produced?


  Combustion in excess oxygen and it produces carbon dioxide and water
• What is incomplete combustion and what does it produce?


  combustion in limited oxygen and it produces carbon soot and carbon monoxide
• How is carbon soot formed and what problems does it cause?


  Formed: Incomplete combustion

  Problems: Asthma and other diseases
• How is carbon monoxide formed and what problems does it cause?


  Formed: Incomplete combustion

  Problem: Toxic
• How is Carbon dioxide formed and what problems does it cause?


  Formed: complete combustion

  Problems: Enhances greenhouse effect
• How is sulfur dioxide formed and what problems does it cause?


  Formed: combustion with impurities

  Problems: Acid rain and respiratory problems
• How are oxides of nitrogen formed and what problems does it cause?


  Formed: Reactions of air under vigorous conditions

  Problems: respiratory problems and acid rain
• Why is carbon monoxide toxic?


  Binds to hemoglobin in the same way oxygen does - this means oxygen cannot bind to the hemoglobin
• What are the trends within hydrocarbons?


  - As they become bigger they are harder to ignite as the molecules don't vaporize as easily

  - Bigger molecule have larger van der waals forces

  - Bigger molecules have yellow and smokey flames
• How and why is sulfur dioxide removed?


  Spray tower scrubber. As sulfur dioxide is an acidic gas it needs to be neutralised. This is done using limestone slurry (CaCO3)
• What are flue gases and how are they sulfurised?


  Flue gases are gases given out by power stations. They are sprayed by a slurry of calcium oxide and water - this causes calcium sulfite to be formed which can be further oxidised to calcium sulfate