Alcohols

• What is the general formula for alcohols?


  C$n$H$2n+$$1$OH
• How are alcohols named?


  They have the ending -ol, with the position number for the OH group added if necessary.
• What is the name of the compound with the structure CH3CH(OH)CH2CH3?

  butan-2-ol
• What prefix is used for an -OH group when there are other functional groups that need a suffix ending?


  The prefix hydroxy- is used.
• What is the name of the compound CH3CH(OH)COOH?


  1. hydroxypropanoic acid
• How are multiple -OH groups indicated in alcohol naming?

  By using di, tri, etc., and adding 'e' to the stem name.
• What is the name of the compound with the structure CH3CH(OH)CH2CH2OH?

  ethane-1,2-diol
• What defines a primary alcohol?


  It has 1 carbon attached to the carbon adjoining the oxygen.
• What defines a secondary alcohol?


  It has 2 carbons attached to the carbon adjoining the oxygen.
• What defines a tertiary alcohol?


  It has 3 carbons attached to the carbon adjoining the oxygen.
• What is the bond angle for H-C-H and C-C-O in alcohols?


  109.5°
• What is the bond angle for H-O-C in alcohols?


  104.5°
• Why do alcohols have relatively low volatility and high boiling points?


  Due to their ability to form hydrogen bonds between alcohol molecules.
• Why can smaller alcohols dissolve in water?


  Because they can form hydrogen bonds with water molecules.
• What is the oxidizing agent that causes alcohols to oxidize?


  Potassium dichromate (K$2$Cr$2$O$7$)
• What is the reaction of a primary alcohol when partially oxidized?


  It forms an aldehyde.
• What reagent is used for the partial oxidation of primary alcohols?


  Potassium dichromate (VI) solution and dilute sulfuric acid.
• What are the conditions for the partial oxidation of primary alcohols?


  Warm gently and distill out the aldehyde as it forms.
• What is the name of an aldehyde?


  It ends in -al.
• What is the observation when primary alcohols are oxidized with potassium dichromate?


  The orange dichromate ion reduces to the green Cr$3+$ ion.
• How can the oxidation equation for a primary alcohol be simplified?


  By using [O] to represent O from the oxidizing agent.
• How should aldehydes be written in condensed formulae?


  As CHO, not COH.
• What is the purpose of distillation in organic chemistry?


  To separate an organic product from its reacting mixture.
• What should be done to maximize yield during distillation?


  Collect only the distillate at the approximate boiling point of the desired aldehyde.
• Where should the bulb of the thermometer be placed in a distillation setup?


  At the T junction connecting to the condenser.
• Why does water enter the bottom of the condenser during distillation?


  To go against gravity for more efficient cooling and to prevent backflow.
• Why are electric heaters used in heating organic chemicals?


  Because organic chemicals are highly flammable and could ignite with a naked flame.
• How can the collection flask be cooled to improve yield during distillation?


  By cooling it in ice.
• What is the reaction of a primary alcohol when fully oxidized?


  It forms a carboxylic acid.
• What are the conditions for the full oxidation of primary alcohols?


  Use an excess of dichromate and heat under reflux.
• What is the observation when primary alcohols are fully oxidized with potassium dichromate?


  The orange dichromate ion reduces to the green Cr$3+$ ion.
• What is reflux used for in organic chemistry?

  To prevent organic vapors from escaping by condensing them back to liquids.
• What should never be done with the end of the condenser during reflux?

  It should never be sealed.
• What is the purpose of adding anti-bumping granules in distillation and reflux?

  To prevent vigorous, uneven boiling by making small bubbles form instead of large bubbles.
• What is the reaction of secondary alcohols when oxidized?

  They form ketones.
• What reagent is used for the oxidation of secondary alcohols?

  Potassium dichromate (VI) solution and dilute sulfuric acid.
• What are the conditions for the oxidation of secondary alcohols?

  Heat under reflux.
• What is the name of a ketone?


  It ends in -one.
• What happens to ketones under oxidation conditions?


  They cannot be further oxidized.
• How can aldehydes be distinguished from ketones?


  Aldehydes can be further oxidized to carboxylic acids, while ketones cannot.