Iodine has the symbol I.
From the Greek word "iodes" meaning "violet"
and discovered by Bernard Courtois in France in 1811 .
Atomic Number = 53, Atomic Mass = 126.9, 53 protons, 53 electrons,
Most common use:
- iodide, and thyroxin which contains iodine, are used internally
- A solution of KI and iodine in alcohol is used as a disinfectant
for external wounds.
-silver iodide is used in photography
- added to table salt for nutrition to stop goiter in the thyroid
- deep blue color in a starch solution is a sign of the free
Iodine, I2 is not reactive towards with oxygen,
O2, or nitrogen, N2.
Iodine, I2, reacts with water to produce hypoiodite,
OI-. The position of the equilibrium depends very
much upon the pH of the solution.
In the graphic on the left, iodine element reacts with zinc
metal to form zinc iodide. The reaction is so exothermic that
part of the iodine element solid is vaporized to iodine violet