Chapter 14 - Alcohols Flashcards
What functional group makes an alcohol?
OH (hydroxyl group)
Compare alcohols to alkanes
Alcohols are less volatile, have higher melting points and are more water soluble than alkanes
Why do alcohols have a higher boiling point that alkanes?
Alcohols have intermolecular hydrogen bonds which are stronger and require more energy to break than the weaker London forces in alkanes
What does it mean for a compound to be water soluble?
It means that hydrogen bonds can form between the molecules in the compound and molecules of water
How does solubility of alcohols relate to its chain length?
As the length of the alcohols chain increases, the solubility decreases (as the influence of the OH group lowers)
What are the 3 classifications of an alcohol?
Primary, secondary and tertiary
What is a primary alcohol?
An alcohol where the OH group is bonded to a carbon with one alkyl group (CH3/4) attached
What is a secondary alcohol?
An alcohol where the OH group is bonded to a carbon with two alkyl groups (CH3/4) attached
What is a tertiary alcohol?
An alcohol where the OH group is bnded t a carbon with three alkyl groups (CH3/4) attached
Describe combustion of alcohols?
Where alcohols completely burn in excess oxygen to produce carbon dioxide and water, also releases a large amount of heat energy
What types of alcohols can be oxidised?
Primary and secondary
What is used to oxidise alcohols?
Potassium dichromate (K2Cr2O7) (or less likely to be used, dilute sulfuric acid (H2SO4))
How can you produce an aldehyde (H-C=O)from a primary alcohol?
By gently heating the alcohol with [O] (K2Cr2O7), then removing the aldehyde from the reaction mixture through distillation
How can you produce a carboxylic acid (HO-C=O) from a primary alcohol?
Heating an alcohol under reflux conditions with 2[O] (K2Cr2O7)
What happens when you oxidise a secondary alcohol under reflux?
It forms a ketone (C=O)
