What is chlorine at its natural form, elemental form making up an object and its compound form?

and in its compund form, it needs to be making up an object? thanks a lot, i need this for my science project.What is chlorine at its natural form, elemental form making up an object and its compound form?
Chlorine (Cl) in its elemental form is a potent poison. So stay away from it. When it comes in contact with a rear earth metal Sodium (Na) it forms a common table salt (NaCl)What is chlorine at its natural form, elemental form making up an object and its compound form?
http://en.wikipedia.org/wiki/Chlorine