Observation

majority of the candidates applied theoretical knowledge by writing addition of iodine solution to starch. They assumed that the sample was starch.

The expected answer include:

To a portion of the sample

(a) Add Fehlings solution/Benedict solution/Tollen’s reagent and heat  formation of brick red precipitate indicates the presence of glucose.
No visible reaction indicates sucrose/starch.

(b) To another portion of the sample add few drops of iodine solution.  Formation of blue black colouration indicates the presence of starch .No visible reaction indicates glucose/sucrose .