![]() Indeed, scandium produces no spectroscopic lines, so could not be identified by this method of analysis. He even made a prediction related to the discovery of the element - that it would not be discovered spectroscopically. He predicted that the carbonate of ekaboron would not be soluble in water, which scandium carbonate is not. Some of Mendeleev's predictions were even more detailed. For example, Mendeleev predicted the element's molecular weight would be 44 and that it would form one oxide with formula Eb 2O 3 scandium has molecular weight 45, and forms scandium oxide, Sc 2O 3. The metal of this new oxide, scandia, was indeed found to have similar properties to this "ekaboron", thus demonstrating the power of Mendeleev's construction. One of these four, Mendeleev predicted, should have properties very similar to boron, and he named this element "ekaboron", meaning "like boron". The discovery of this element was especially notable, as, seven years previously, Mendeleev had used his periodic table to predict the existence of ten as yet unknown elements, and for four of these, he predicted in great detail the properties they should have. Nilson named this oxide scandia, after Scandinavia. Nilson was a student of the legendary Jacob Berzelius, himself discoverer of many elements. In 1879, Lars Nilson, isolated the oxide of a new metal element from the minerals gadolinite and euxenite. 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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