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Chapter 14 - Alcohols - Coggle Diagram

- - - - Gently heat a primary alcohol with acidifed potassium dichromate
      - To avoid making carboxylic acids, the aldehyde is distilled out as it forms, to prevent any further reaction with oxidising agent
      - Dichromate ions change colour from orange to green
    - - Primary alcohols is heated strongly under reflux, with excess acidified potassium dichromate
      - Excess acidified potassium dichromate ensures all the alcohol is oxidised
      - Heating under reflux ensures an aldehyde formed initially in the reaction also undergoes oxidation to the carboxylic acid
- - - - Alkanes have non-polar bonds while alcohols have a polar O-H bond so they're polar
      - Weak London forces in both molecules, but there are muhch stronger hydrogen bonds between polar O-H groups
    - - How easily something is converted from a liquid to a gas
      - In alcohols, the hydrogen bonds have to be broken, which requires more energy that overcoming weaker london forces in alkanes
      - Alcohols have a lower volatility than the alkanes with the same number of carbon atoms
    - - Compound that can form hydrogen bonds with water is far more water-soluble than a compound that can't
      - Alkanes are non polar and cannot form hydrogen bonds with water
      - Alcohols like methanol and ethanol are completely soluble in water
      - As chain increases in size, influence of -OH becomes smaller and the solubility of longer chain alcohols becomes more like that of hydrocarbons - solubility decreases