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Fermium is produced by the bombardment of lighter actinides with neutrons in a nuclear reactor. Fermium-257 is the heaviest isotope that is obtained via neutron capture, and can only be produced in picogram quantities.
The Gmelin rare earths handbook lists 1522 °C and 1550 °C as two melting points given in the literature, the most recent reference [Handbook on the chemistry and physics of rare earths, vol.12 (1989)] is given with 1529 °C.
Einsteinium's melting point (860 °C) is also relatively low – below californium (900 °C), fermium (1527 °C) and holmium (1461 °C). [ 5 ] [ 27 ] Einsteinium is a soft metal, with a bulk modulus of only 15 GPa, one of the lowest among non- alkali metals .
However, at very high pressures higher melting temperatures are generally observed as the liquid usually occupies a larger volume than the solid making melting more thermodynamically unfavorable at elevated pressure. If the liquid has a smaller volume than the solid (as for ice and liquid water) a higher pressure leads to a lower melting point.
The classical Stefan problem aims to describe the evolution of the boundary between two phases of a material undergoing a phase change, for example the melting of a solid, such as ice to water. This is accomplished by solving heat equations in both regions, subject to given boundary and initial conditions. At the interface between the phases ...
Liquid francium—if created—should have a surface tension of 0.05092 N/m at its melting point. [10] Francium's melting point was estimated to be around 8.0 °C (46.4 °F); [11] a value of 27 °C (81 °F) is also often encountered. [8] The melting point is uncertain because of the element's extreme rarity and radioactivity; a different ...
For example, the melting point of silicon at ambient pressure (0.1 MPa) is 1415 °C, but at pressures in excess of 10 GPa it decreases to 1000 °C. [13] Melting points are often used to characterize organic and inorganic compounds and to ascertain their purity. The melting point of a pure substance is always higher and has a smaller range than ...
Ununennium is predicted to have a melting point between 0 °C and 30 °C: thus it may be a liquid at room temperature. [6] It is not known whether this continues the trend of decreasing melting points down the group, as caesium's melting point is 28.5 °C and francium's is estimated to be around 8.0 °C. [ 88 ]