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Pressure-temperature phase diagram of bismuth. T C refers to the superconducting transition temperature. Bismuth is a brittle metal with a dark, silver-pink hue, often with an iridescent oxide tarnish showing many colors from yellow to blue. The spiral, stair-stepped structure of bismuth crystals is the result of a higher growth rate around the ...
Pewter (/ ˈ p juː t ər /) is a malleable metal alloy consisting of tin (85–99%), antimony (approximately 5–10%), copper (2%), bismuth, and sometimes silver. [1] In the past, it was an alloy of tin and lead , but most modern pewter, in order to prevent lead poisoning , is not made with lead.
Bismuth chloride (or butter of bismuth) is an inorganic compound with the chemical formula BiCl 3. It is a covalent compound and is the common source of the Bi 3+ ion. In the gas phase and in the crystal, the species adopts a pyramidal structure, in accord with VSEPR theory .
Bismuth oxide, Bi 2 O 3 has five crystallographic polymorphs. The room temperature phase, α-Bi 2 O 3 has a monoclinic crystal structure. There are three high temperature phases, a tetragonal β-phase, a body-centred cubic γ-phase, a cubic δ-Bi 2 O 3 phase and an ε-phase. The room temperature α-phase has a complex structure with layers of ...
Notably, this is the case of water, as illustrated graphically to the right, but also of Si, Ge, Ga, Bi. With extremely large changes in pressure, substantial changes to the melting point are observed. 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.
Melting ice cubes illustrate the process of fusion. Melting, or fusion, is a physical process that results in the phase transition of a substance from a solid to a liquid. This occurs when the internal energy of the solid increases, typically by the application of heat or pressure, which increases the substance's temperature to the melting point.
At the peritectic decomposition temperature the compound, rather than melting, decomposes into another solid compound and a liquid. The proportion of each is determined by the lever rule. In the Al-Au phase diagram, for example, it can be seen that only two of the phases melt congruently, AuAl 2 and Au 2 Al, while the rest peritectically decompose.
Tammann temperature was pioneered by German astronomer, solid-state chemistry, and physics professor Gustav Tammann in the first half of the 20th century. [1]: 152 He had considered a lattice motion very important for the reactivity of matter and quantified his theory by calculating a ratio of the given material temperatures at solid-liquid phases at absolute temperatures.