14.2 Reactions of Alcohols Flashcards
(24 cards)
What is one type of reaction alcohols can undergo if there is heat and a plentiful supply of oxygen?
Combustion
What are the products produced from the combustion of alcohol?
Carbon dioxide and water
The longer the chain in the combusted alcohol…
… the more heat is released per mole
What types of alcohols can be oxidised?
Primary and secondary alcohols
What kind of catalysts are used when oxidising alcohols?
Acidified catalysts
What are the usual catalysts used in the oxidation of alcohols?
-Potassium dichromate(VI) (K2Cr2O7) acidified with sulphuric acid
What colour will the solution of dichromate ions turn into when the alcohol is oxidised?
-The solution turns green
What are dichromate ions reduced to?
Chromium (III) ions
What two products can primary alcohols be oxidised to?
-Aldehydes
-Carboxylic acids
What conditions can create an aldehyde?
Gently heating primary alcohols and distilling the reaction mixture
What conditions can create a carboxylic acid?
Strongly heating a primary alcohol under reflux with an excess of the oxidising agent.
What product is formed from the oxidation of secondary alcohols?
Ketones
Can ketones be oxidised further?
No
How are ketones prepared?
Heating secondary alcohols under reflux (so the reaction goes to completion)
What does the symbol [O] mean?
[O] represents the oxidising agent
Can tertiary alcohols be oxidised?
No.
What is the suffix for ketones?
-one
What is the suffix for carboxylic acids?
-oic acid
What is the suffix for aldehydes?
-al
What is a dehydration reaction?
When a molecule is removed from a molecule
What are the products created when an alcohol undergoes dehydration?
An alkene and water
What catalysts are usually used when dehydrating an alcohol?
-Concentrated sulphuric acid
-Concentrated phosphoric acid
What reaction allows haloalkanes to be created from alcohols?
Substitution reactions
What are the two main products produced when creating a haloalkane through substitution?
A haloalkane and water
