Chlorine is a pale green-yellow gas, according to About.com. Its name is derived from the Greek word "khloros," which means "greenish-yellow." Chlorine has an atomic number of 17 and atomic weight of 35.4527. Its symbol is Cl.
The gaseous element chlorine was discovered by Carl Wilhelm Scheele in Sweden in 1774. It has a melting point of minus 100.98 C and boiling point of minus 34.6 C. Chlorine is not often found by itself in nature. Rather, chlorine is often found combined with sodium to form sodium chloride, which is commonly known as salt. Chlorine is often used to disinfect drinking water and in the production of products such as dyes and textiles.