N5 Chemistry/Physics
S
Past paper of the week:
2018 past paper
Oxidising agent:
Hot copper(Il) oxide or acidified dichromate (VI) solutions can be used to oxidise:
primary alcohols to aldehydes and then to carboxylic acids
secondary alcohols to ketones
During these reactions black copper(Il) oxide forms a brown solid,
and orange dichromate solution turns green.
Tertiary alcohols cannot be oxidised using these oxidising agents.
Oxidising agents can be used to differentiate between an aldehyde and a ketone. With an aldehyde:
blue Fehling's solution forms a brick red precipitate
Clear, colourless Tollens' reagent forms a silver mirror
Upcoming lesson:
Physics - electricity