Period 3 element in 1810, who named it chlorine, from the Greek word χλωρος (chlōros), meaning "green-yellow." Chlorine is a component of various compounds, including table salt. It is the second most abundant halogen and 21st most abundant chemical element in Earth's crust. The great oxidizing potential of chlorine led it to its bleaching and disinfectant uses, as well as uses of an essential reagent in the chemical industry. As a common disinfectant, chlorine compounds are used in swimming pools to keep them clean and sanitary. In the upper atmosphere, chlorine-containing molecules such as chlorofluorocarbons have been implicated in ozone depletion. "Argon" (symbol
Greek name Modern Greek Enlightenment and the development of Greek nationalism, names from antiquity became popular again. Family names may be patronymic in origin or else based on occupation, location, or personal characteristic. These origins are often indicated by prefixes or suffixes. Traditionally a woman used a feminine version of her father's family name, replacing it with a feminine version of her husband's family name on marriage. In modern Greece, a woman keeps her father's family name for life but may use a husband's name. In official documents in modern Greece, people are given three names: a given name, a patronymic and