# Benedicts reagent is an indicator for the presence of what in a solution?

Mar 11, 2018

Reducing sugar and reducing sugar like substances like creatinine,uric acid,homogentisic acid etc.

#### Explanation:

Benedict's reagent conatins, $C u S {0}_{4} , N a - c a r b o n a t e \mathmr{and} N a - c i t r a t e$

In presence of alkaline media created due to $N a - c a r b o n a t e$ reducing sugar undergoes ene-diol transformation as a result of this $C {u}^{+ 2}$ in $C u S {O}_{4}$ (blue) gets reduced to $C {u}^{+}$ of $C {u}_{2} O$ (red).

$N a - c i t r a t e$ causes slow release of $C {u}^{+ 2}$ from $C u S {O}_{4}$

So,change in colour of the solution is indicated as a positive test.

Now,this change in color proceeds through a steps of color changes,which corresponds roughly to certain amount of reducing sugar present.

Blue - 0%

Green -0.5 g %

Yellow - 1 g%

Oran g e - 1.5 g%

Red - 2 g%

Brick Red - _-^> 2.5 g %

So,Benedict's test is also called Semiquantitative test.