The atomic number or nuclear charge number (symbol Z) of a chemical element is the charge number of an atomic nucleus. For ordinary nuclei composed of...

is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). The definitive visualisation of...

mass number (symbol A, from the German word: Atomgewicht, "atomic weight"), also called atomic mass number or nucleon number, is the total number of protons...

lowest mass) has an atomic weight of 1.007825 Da. The value of this number is called the atomic mass. A given atom has an atomic mass approximately equal...

atomic number, denoted by Zeff, may refer to: Effective nuclear charge of an individual atom, as felt by electrons within that atom Effective atomic number...

contributions. Thus, the numeric value of the atomic mass when expressed in daltons has nearly the same value as the mass number. Conversion between mass in kilograms...

Lead is a chemical element; it has symbol Pb (from Latin plumbum) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead...

chemical element with the symbol Au (from the Latin word aurum) and the atomic number 79. In its pure form, it is a bright, slightly orange-yellow, dense...

unique atomic number (Z) representing the number of protons in its nucleus. All elements have multiple isotopes, variants with the same number of protons...

identified by the number of protons in the nuclei of their atoms, known as the element's atomic number. For example, oxygen has an atomic number of 8, meaning...