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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.
The melting point of ordinary hexagonal ice falls slightly under moderately high pressures, by 0.0073 °C (0.0131 °F)/atm [h] or about 0.5 °C (0.90 °F)/70 atm [i] [53] as the stabilization energy of hydrogen bonding is exceeded by intermolecular repulsion, but as ice transforms into its polymorphs (see crystalline states of ice) above 209.9 ...
Inorganic compounds with simple ions typically have small ions, and thus have high melting points, so are solids at room temperature. Some substances with larger ions, however, have a melting point below or near room temperature (often defined as up to 100 °C), and are termed ionic liquids . [ 64 ]
Ionic solids are typically of intermediate strength and extremely brittle. Melting points are typically moderately high, but some combinations of molecular cations and anions yield an ionic liquid with a freezing point below room temperature. Vapour pressures in all instances are extraordinarily low; this is a consequence of the large energy ...
When it is converted to the covalent red phosphorus, the density goes to 2.2–2.4 g/cm 3 and melting point to 590 °C, and when white phosphorus is transformed into the (also covalent) black phosphorus, the density becomes 2.69–3.8 g/cm 3 and melting temperature ~200 °C. Both red and black phosphorus forms are significantly harder than ...
This term was later used as a generic term to describe all the elements in the chlorine family (fluorine, bromine, iodine), after a suggestion by Jöns Jakob Berzelius in 1826. [ 24 ] [ 25 ] In 1823, Michael Faraday liquefied chlorine for the first time, [ 26 ] [ 27 ] [ 28 ] and demonstrated that what was then known as "solid chlorine" had a ...
Its predicted melting and boiling points are 52±15 °C and 177±10 °C respectively, so that it is probably neither noble nor a gas; it is expected to have a density of about 6.6–7.4 g/cm 3 around room temperature. It is expected to have a barely positive electron affinity (estimated as 5 kJ/mol) and a moderate ionisation energy of about 860 ...
2 has the most ionic character, while the others (ZnCl 2, ZnBr 2, and ZnI 2) have relatively low melting points and are considered to have more covalent character. [68] In weak basic solutions containing Zn 2+ ions, the hydroxide Zn(OH) 2 forms as a white precipitate. In stronger alkaline solutions, this hydroxide is dissolved to form zincates ...