Chemical element whole number. For example, the relative atomic mass of chlorine is 35.453 u, which differs greatly from a whole number as it is an average of about 76% chlorine-35 and 24% chlorine-37. Whenever a relative atomic mass value differs by more than 1% from a whole number, it is due to this averaging effect, as significant amounts of more than one isotope are naturally present in a sample of that element. Chemists and nuclear scientists have different definitions of a "pure element". In chemistry, a pure element means a substance whose atoms all (or in practice almost all) have the
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