Noble metal are covered by carbon monoxide very quickly. Metallic elements, including metalloids (metals usually considered noble bolded, predictions for superheavy elements italicised): The columns "group" and "period" denote its position in the periodic table, hence electronic configuration. The simplified "reaction"s, listed in the next column, can also be read in detail from the Pourbaix diagrams of the considered element in water. Finally the column "potential" indicates the electric potential of the element measured against a Standard hydrogen electrode. All missing elements in this table are either not metals or have a negative standard potential. Arsenic, antimony and tellurium are considered to
Crystal detector voltage of around 0.2V from a battery to make it more sensitive. Although the zincite-chalcopyrite "Perikon" was the most widely used crystal-to-crystal detector, other crystal pairs were also used. Zincite was also used with carbon, galena, and tellurium. Silicon was used with arsenic, antimony and tellurium crystals. During the first three decades of radio, from 1888 to 1918, called the "wireless telegraphy" or "spark" era, primitive radio transmitters called spark gap transmitters were used, which generated radio waves by an electric spark. These transmitters were unable to produce the continuous sinusoidal waves which are used to transmit audio (sound) in