Why does chlorine exist as a compound in nature?

Remember its electronic configuration is 1s2 2s2 2p6 3s2 3p5, thus a total of 17 electrons. It just needs one more electron to attain the nobel gas configuration to attain the stable structure. It is easier to give off or to gain one electron for this purpose, hence, such compounds are highly reactive and can easily attain the stable configuration by reacting with their counterparts. Hence chlorine typically would like to exist as a compound in nature.