Iodine is a chemical element with symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a lustrous, purple-black metallic solid at a standard conditions that sublimes readily to form a violet gas. The elemental form was discovered by the French chemist Bernard Courtois in 1811.
Definition of CHOLLA. : any of numerous shrubby opuntias chiefly of the southwestern United States and Mexico that have needlelike spines partly enclosed in a papery sheath and cylindrical joints âcalled also cholla cactus.
It can grow to 60 feet in height. A barrel cactus can grow to about 10 feet in height. The jumping cholla can grow to about 5 feet in height. Their spines fall off so easily that they are called jumping chollas as the fine thorns seem to leap off when a person is standing close by.