Welcome to "A Visual Interpretation of The Table of Elements", the most striking version of the periodic table on the web. Images © Murray Robertson 1999-2011 Text © The Royal Society of Chemistry 1999-2011 However, at present we can all agree that there is more to diamond than just a pretty face! This material will be keeping chemists, materials scientists, physicists and engineers busy for many years to come. Challenges still remain to understand the complex chemistry of the intercrystalline boundaries and surface chemistry of the films and to learn how best to exploit them. While they may not be as pretty, these diamond films can be deposited on a range of surfaces of different size and shapes and so hugely increase the potential applications of diamond. The films are polycrystalline, consisting of crystallites in the micron size range so lack the clarity and brilliance of gemstone diamond. Actually both graphite and diamond are initially formed, but under these highly reactive conditions, the graphitic deposits are etched off the surface, leaving only the diamond. The carbon-based molecules then deposit on a surface to form a coating or thin film of diamond. A gas mixture of 99 % hydrogen and 1 % of methane is used and some activation source like a hot filament employed to produce highly reactive hydrogen and methyl radicals. It is this metastability of diamond that is exploited in chemical vapour deposition. 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.
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