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    When I use Tollen's regent to distinguish between aldehydes and ketones, a formation of a silver mirror or precipitate is expected to say this is an aldehyde, and the opposite is true for ketones.

    The question is, why does this happen to aldehydes and ketones? What is the explanation?

    Thanks.
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    (Original post by SWEngineer)
    When I use Tollen's regent to distinguish between aldehydes and ketones, a formation of a silver mirror or precipitate is expected to say this is an aldehyde, and the opposite is true for ketones.

    The question is, why does this happen to aldehydes and ketones. What is the description?

    Thanks.
    Aldehydes are reducing agents - they themselves get oxidised to acids in the reaction.

    Ketones cannot be oxidised to acids, so they are NOT reducing agents.

    Aldehydes reduce complexed silver from Ag+ to Ag(s) forming a silver mirror.
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    Tollens reagent is a mild oxidant and so aldehydes get oxidised (reacts) and ketones don't (can't be oxidised easily).

    edit: I've gotten slow :p:
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    Thanks a lot for your replies.
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    Anyone has the answer as to why the silver coating/mirror, sticks to the side of the test tube or container that it's in?
 
 
 
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