Lugol’s
solution is an aqueous solution of Iodine and Potassium iodine with a precise ratio of 1:2. It is also
referred to as Iodone
-
Potassium solution. Lugol’s solution contains poly Iodine ions. Iodine itself is purely
soluble in water
. But in the presence of i
odide it forms soluble tri
-
iodid
e
and penta
-
iodide ions:
I
2
+ I
-
[I
3
]
-
and I
2
+ [I
3
]
-
[I
5