Past paper of the week:

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