B3 - Alcohol Reactions Flashcards
(12 cards)
What mixture and colour change can show the oxidation of an alcohol?
If the alcohol is in a mixture of potassium dichromate (VI) with dilute sulfuric acid is oxidised, the ORANGE solution containing dichromate (VI) ions is reduced to a GREEN solution containing chromium (III) ions.
What can primary alcohols be oxidised to?
Aldehyde or carboxylic acids.
How do you produce an aldehyde?
Gently heat a primary alcohols with acidified potassium dichromate and DISTIL.
How do you produce a carboxylic acid?
Strongly heat a primary alcohol UNDER REFLUX with an excess of acidified potassium dichromate
What are secondary alcohols oxidised to?
Ketones.
How do you produce a ketone?
Heat a secondary alcohol UNDER REFLUX with the oxidising mixture.
What are tertiary alcohols oxidised to?
Nothing. Tertiary alcohols do not undergo oxidation reactions.
What is produced when alcohols are dehydrated?
Alkenes.
State any conditions required for the dehydration of alcohols:
- Heat under reflux
- Acid catalyst (conc sulfuric acid or conc phosphoric acid)
What type of reaction is the dehydration of alcohols?
An elimination reaction.
How can you form a haloalkane from an alcohol?
The alcohol is heated under reflux with sulfuric acid and a sodium halide.
What is formed when an alcohol is converted to a haloalkane?
The hydrogen halide in situ (in place of the sodium halide).
