Simple chemical tests Tollens’ test

Permanganate and dichromate distinguish an aldehyde from a ketone but not from primary or secondary alcohols. Tollens reagent is a selective (mild) oxidizing reagent that forms the basis for a simple chemical test to distinguish aldehydes from ketones as well as from primary and secondary alcohols. 

As we saw on page 236, aldehydes can be further oxidised to form carboxylic acids, but ketones cannot be oxidised easily. We can use this difference to distinguish between an aldehyde and a ketone in simple chemical tests. The two tests most commonly used involve Tollens reagent and Fehling s solution. 

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