Chemical Properties
Chlorine has seven valence electrons and therefor is seeking to combine with any other substance on the periodic table. It is very unstable and is never found alone. It is always combined with some other element.
The most abundant form of chlorine is found in NaCl, or table salt.
Chlorine can be formed from the oxidation of hydrochloric acid and manganese dioxide. The greenish, yellow gas is two and a half times as heavy as air and therefor it will sink and can be placed into a flask or jar. This is almost the only time that chlorine can be seen in its pure form. If it is on its own, it will combine with other elements to become more stable.