Figure of the month: 79
News Arnulf Hinkel, Finance journalist – 01.01.2017
Gold is not only a portfolio-stabilizing element valued by investors but also a chemical one that, alongside the coinage metals copper and silver, belongs to the first group (group 11) in the periodic table. Gold goes with the element symbol Au (for "Aurum", Latin for "gold") and the atomic number 79. To understand the meaning of this number, it is important to know that the periodic table breaks down all chemical elements according to their chemical properties by period trends, main groups and subgroups, and represents them in ascending order according to their respective nuclear charge. The nuclear charge is the charge of an atomic nucleus, which can be determined as the product of the number of protons in the atomic nucleus and the elementary charge. The elementary charge is the smallest natural electrical charge quantity. As a rule, the nuclear charge number corresponds to the order number of an element. Using the order number, a chemical element can be determined. In addition, the order number gives information about the number of electrons of an element, provided that it is in an elementary (non-ionized) state. Containing 79 protons in its atomic nucleus, gold is one of the elements with a high nuclear charge and it is a transition metal, as are its periodic table "neighbors" platinum, with the order number 78, and mercury with 79. Hydrogen with the order number 1 contains the lowest nuclear charge, followed by the alkali metals lithium and beryllium with the respective order numbers 2 and 3. The natural element with the second-highest nuclear charge in the periodic table is also an alkali metal: radium with the order number 88. The natural element sporting the highest nuclear charge is the rare element uranium at 91. Uranium is radioactive, as well as the elements with an even higher number of protons in the atomic nucleus, all of which are artificially produced, such as oganesson with the order number 118, which can be produced exclusively by direct nuclear fusion.