Plate tectonics is a scientific theory that describes the large-scale motion of Earth's lithosphere. Plates at our planet’s surface move because of the intense heat in the Earth’s core that causes molten rock in the mantle layer to move.
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The density : 21.63 g/L
<h3>Further explanation</h3>
The gas equation can be written

where
P = pressure, atm
V = volume, liter
n = number of moles
R = gas constant = 0.08206 L.atm / mol K
T = temperature, Kelvin
T = 65+273=338 K
P=2.36 atm
MW Iodine gas (I₂)=254
The density :

Stored in porous soil and rock hope it helps