Black
Ans2:It is very unlikely that a ripe banana will have enough starch to turn iodine black. When iodine turns black, it is a positive test for the presence of starch.Starches turn blue-black when stained with iodine (which usually stains things a reddish-brown or amber color).Iodine turns blue black when starch is present
Black
yellow
purple
Black
blue
A banana will slowly turn black as it starts to go rotten.
blue/black
The water solution of iodine turn blue litmus paper to red.
dark blue - purple
If a substance didn't turn blue or black with iodine, it means that it didn't form any complex with iodine. When iodine forms a complex with the substance, the complex is generally blue in color.
Iodine is used as an indicator for starch. When a substance has iodine added to it, then it will turn into a dark blue color. This is a sign that the substance indeed has starch in it.