Ketones do not reduce Tollen's reagent. ...

Ketones do not reduce Tollen's reagent. Why is fructose a reducing sugar ?

Text Solution

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The reaction with Tollen's reagent i.e., Ammoniacal silver nitrate is carried in the basic medium in which fructose is converted into enolic form which exists in equilibrium with glucose. Therefore, fructose behaves as a reducing sugar.

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Reducing sugar is

Glycogen

Sucrose

Lactose

All of the above

Tollen's reagent is reduced by

HCOOH

`CH_(3)COOH`

`CH_(2)ClCOOH`

`C C l_(3) COOH`

Ketones do not reduce Tollen's reagents, but fructose with a keto group reduces it. It is attributed to.

Enolisation of keto group of fructose and then, its transformation into aldehyde group in presence of `OH^(-)` which is present in Tollen's reagent.

`gt CHOH` group which is also oxidised to keto group

Both statements are correct

None of the statement is correct