alcohols true

• Alcohol

  An alkane where a hydrogen is replaced by a hydroxyl group
• General formula for alcohols

  CnH(2n+1)OH
• Classifying alcohols

  Primary, secondary, or tertiary based on the number of carbons bonded to the carbon atom with the hydroxyl group
• Properties of alcohols (and diols)

  Contain an oxygen-hydrogen bond leading to hydrogen bonding between alcohol molecules, tend to be liquid at room temperature, melting and boiling points increase with the length of the carbon chain, solubility decreases as the length of the carbon chain increases
• Carbonyl compound

  Molecule containing a carbonyl group, which is a carbon-oxygen double bond
• To draw a carbonyl compound

  Draw the carbon chain, Add the carbonyl group to the correct carbon, If drawing a carboxylic acid, add the hydroxyl group
• Aldehydes, Ketones, and Carboxylic Acids are types of carbonyl compounds
• Properties of Carbonyl Compounds

  Experience Van der Waals forces, dipole-dipole forces, carboxylic acids have a hydroxyl group leading to hydrogen bonding, melting and boiling points increase with the length of the carbon chain, solubility decreases as the molecule gets longer
• To draw a carbonyl compound

  1. Draw the carbon chain

  2. Add the carbonyl group to the correct carbon

  3. If you’re drawing a carboxylic acid, add the hydroxyl group
• Carbonyl group

  A carbon-oxygen double bond
• Carboxylic acids

  Compared to aldehydes and ketones with the same number of carbons, carboxylic acids have higher melting and boiling points
• Length of the carbon chain

  As the length of the carbon chain increases, the melting and boiling points of carbonyl compounds also increase
• Small carbonyl compounds are highly soluble in water
• Solubilityof Alcohols

  Decreases as the molecule gets longer
• Carboxylic acids are more soluble than aldehydes and ketones of similar lengths</b>
• Why do ketones not undergo additional oxidation?

  ketones are tertiary and have no available hydrogen on the carbon to undergo further oxidation
• What is the reagent to oxidise alcohols?

  Potassium dichromate
• What is the test for alcohols?

  Add potassium dichromate that's not in excess

  if the solution turns from orange to green then a primary or secondary alcohol is present
• 2 methods of producing ethanol?

  Fermentation

  Hydration
• Conditions for fermentation?

  presence of yeast and glucose

  Anaerobic conditions

  temperature between 25-40 C
• Disadvantages of the use of crops for the production of ethanol:

  • Growth is subject to the environment
  • Reduces land available for food growth
  • Requires the use of fossil fuels
  • Not carbon neutral
  • Requires significant processing after production to separate the ethanol from water
• Advantages of the hydration of ethene method for making ethanol:

  • Faster reaction
  • higher atom economy
  • Continuous process
• selected method to produce aldehydes from alcohols?

  Distillation
• Selected method to produce carboxylic acid/ketones from alcohols?

  Reflux

  excess potassium dichromate
• Forces present between alcohols?

  Van der waals

  Hydrogen bonding
• Carbon neutrality is when the amount of carbon dioxide produced by an activity is equal to the amount removed from the atmosphere
• Reactions showing bioethanol produced via fermentation is carbon neutral:

  Photosynthesis:

  6 CO2 + 6 H2O -> C6H12O6 + 6 O2

  Fermentation:

  C6H12O6 -> 2 C2H5OH + 2 CO2

  Combustion:

  2 C2H5OH + 6 O2 -> 4 CO2 + 6 H2O

  6 mols of CO2 is taken in, in photosynthesis, and 6 mols of CO2 is released in fermentation and combustion
• Hydration of alkenes

  • Acid catalyst
  • Steam
• Hydration of alkenes

  • Acid catalyst
  • Steam