Different types of alcohols C O H H H C H H C H H H C H H C H C H H H O H H C C H C H H H H H C H H O H H Propan-1
Different types of alcohols C O H H H C H H C H H H C H H C H C H H H O H H C C H C H H H H H C H H O H H Propan-1-ol Primary Tertiary alcohols are alcohols where 3 carbon are attached to the carbon adjoining the oxygen Propan-2-ol Secondary methylpropan-2-ol Tertiary Primary alcohols are alcohols where 1 carbon is attached to the carbon adjoining the oxygen Secondary alcohols are alcohols where 2 carbon are attached to the carbon adjoining the oxygen. Oxidation reactions of the alcohols Potassium dichromate K2Cr2O7 is an oxidising agent that causes alcohols to oxidise. The exact reaction, however, depends on the type of alcohol, i.e. whether it is primary, secondary, or tertiary, and on the conditions. Partial Oxidation of Primary Alcohols Reaction: primary alcohol aldehyde Reagent: potassium dichromate (VI) solution and dilute sulphuric acid. Conditions: (use a limited amount of dichromate) warm gently and distil out the aldehyde as it forms: C O C H H H H An aldehyde’s name ends in –al It always has the C=O bond on the first carbon of the chain so it does not need Ethanal an extra number Observation: the orange dichromate ion (Cr2O7 2-) reduces to the green Cr 3+ ion Write the oxidation equations in a simplified form using [O] which represents O from the oxidising agent When writing the formulae of aldehydes in a condensed way write CHO and not COH e.g.CH3CH2CHO N Goalby chemrevise.org 2 propan-1-ol propanal + [O] + H2O CH3CH2CH2OH + [O] CH3CH2CHO + H2O OH + [O] O + H2O C O C H H C H H H H C O H H H C H H C H H H Distillation In general used as separation technique to separate an organic product from its reacting mixture. Need to collect the distillate of the approximate boiling point range of the desired liquid. Water in Water out Liebig condenser thermometer Heat Note the bulb of the thermometer should be at the T junction connecting to the condenser to measure the correct boiling point Note the water goes in the bottom of the condenser to go against gravity. This allows more efficient cooling and prevents back flow of water.