(18) lodine reacts with chlorine to form dark brown iodine monochloride.
12 + Cl2 → 2ICI
This reacts with more chlorine to give yellow iodine trichloride.
An equilibrium forms between these iodine chlorides.
ICU) + Cl2(g) = ICl()
dark brown
yellow
Suggest if the reverse reaction is endothermic or exothermic give reason to your answer

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).

gasoline is a mixture. it contains several different kinds of compounds that can be present in a variety of ratios.