it is used to indicate the presence of starch in a solution . A positive result will indicate a blue/black solution while its absence indicates a brown color.
is used to test for the presence of starch. Starch turns into an intense "blue-black" colour upon addition of aqueous solutions of the triiodide anion, due to the formation of an intermolecular charge-transfer complex. In the absence of starch, the brown color of the aqueous solution remains.
Answer: The reaction of benzene with concentrated sulfuric acid at room temperature produces benzenesulfonic acid. The reaction forms a stable carbocation. SO3 being the electrophile
