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Ketones and Aldehydes Watch

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    Hi, just wondering if I could get some help with these two questions:

    Why do ketones not yield a sliver mirror in the Silver Mirror Test?

    Why is HNO3 suitable for removing the silver mirror?
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    (Original post by gm18)
    Hi, just wondering if I could get some help with these two questions:

    Why do ketones not yield a sliver mirror in the Silver Mirror Test?

    Why is HNO3 suitable for removing the silver mirror?

    What is the reagent in the Silver Mirror Test?
    Spoiler:
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    Tollen's Reagent: [Ag(NH3)2]+

    The silver mirror, is simply a deposit of silver. You are forming silver atoms which, by definition has an oxidation state of 0.

    Look at the oxidation state of silver in the reagent.
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    It is +1.

    So when you form the silver mirror, you're actually reducing it.

    Therefore, the other reactant must be being oxidised.
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    A + B ---> C + D. A is being reduced (gain electrons/gain hydrogen). It gains electrons if B is oxidised (lose electrons/lose hydrogen).

    Aldehydes readily oxidise (to carboxylic acids), but ketones do not. They do not have a hydrogen attached to the carbonyl group. That's why they don't form a silver mirror.
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    thank you! so then why is HNO3 suitable for removing the silver mirror?
 
 
 
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