Janety had managed to develop a means of producing workable platinum using arsenic, and a way to remove the arsenic afterwards with limited success. In 1792 the French Academy of Science obtained a supply of platinum from Marc-Etienne Janety, a master goldsmith in Paris. Of course, that was prior to Lavoisier's beheading at the height of the French Revolution in 1794. Lavoisier succeeded in melting platinum using oxygen to enhance the heat of the furnace but it would still be many years before a process could be found to produce commercial quantities. Seguin later requested details of which fuel could burn sufficiently hot enough, and for further details on creating the hottest flame possible. The French Chemist Lavoisier wrote for help from Josiah Wedgewood, the founder of Wedgewood pottery, asking for a clay that could be used to manufacture vessels that could withstand the high temperatures needed to melt platinum. Three chemists, Lavoisier, Seguin and Musnier began working together in the late 18 th century to improve the design of their furnaces to enable platinum to be melted without the need of fluxes such as arsenic. Platinum's place as a precious metal was first established in the 18 th century by Henrik Sheffer, who succeeded in melting or fusing platinum by adding arsenic. Its high melting point and broad chemical resistance meant that obtaining a pure sample of the metal was difficult. Platinum's properties allowed it to defy identification and classification until the 18 th century. Political stability of top reserve holderĪ percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. The higher the value, the larger risk there is to supply.Ī percentile rank for the political stability of the top producing country, derived from World Bank governance indicators. The percentage of the world reserves located in the country with the largest reserves. The higher the value, the larger risk there is to supply. The percentage of an element produced in the top producing country. Low = substitution is possible with little or no economic and/or performance impact Medium = substitution is possible but there may be an economic and/or performance impact High = substitution not possible or very difficult. The availability of suitable substitutes for a given commodity. A higher recycling rate may reduce risk to supply. The percentage of a commodity which is recycled. The number of atoms of the element per 1 million atoms of the Earth’s crust. This is calculated by combining the scores for crustal abundance, reserve distribution, production concentration, substitutability, recycling rate and political stability scores. The Chemical Abstracts Service registry number is a unique identifier of a particular chemical, designed to prevent confusion arising from different languages and naming systems.ĭata for this section been provided by the British Geological Survey.Īn integrated supply risk index from 1 (very low risk) to 10 (very high risk). Where more than one isotope exists, the value given is the abundance weighted average.Ītoms of the same element with different numbers of neutrons. This is approximately the sum of the number of protons and neutrons in the nucleus. The mass of an atom relative to that of carbon-12. The transition of a substance directly from the solid to the gas phase without passing through a liquid phase.ĭensity is the mass of a substance that would fill 1 cm 3 at room temperature.

The temperature at which the liquid–gas phase change occurs. The temperature at which the solid–liquid phase change occurs. The arrangements of electrons above the last (closed shell) noble gas. These blocks are named for the characteristic spectra they produce: sharp (s), principal (p), diffuse (d), and fundamental (f).

The atomic number of each element increases by one, reading from left to right.Įlements are organised into blocks by the orbital type in which the outer electrons are found. Members of a group typically have similar properties and electron configurations in their outer shell.Ī horizontal row in the periodic table.

Periodic table molar mass