Chemical element hydrogen and deuterium). Thus, all carbon isotopes have nearly identical chemical properties because they all have six protons and six electrons, even though carbon atoms may, for example, have 6 or 8 neutrons. That is why the atomic number, rather than mass number or atomic weight, is considered the identifying characteristic of a chemical element. The symbol for atomic number is "Z". Isotopes are atoms of the same element (that is, with the same number of protons in their atomic nucleus), but having "different" numbers of neutrons. Thus, for example, there are three main isotopes of carbon. All carbon atoms
Given name a name is not assigned at birth, one may be given at a naming ceremony, with family and friends in attendance. In most jurisdictions, a child's name at birth is a matter of public record, inscribed on a birth certificate, or its equivalent. In western cultures, people normally retain the same given name throughout their lives. However, in some cases these names may be changed by following legal processes or by repute. People may also change their names when immigrating from one country to another with different naming conventions. In certain jurisdictions, a government-appointed registrar of births may refuse to