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Periodic Videos (also known as The Periodic Table of Videos) is a video project and YouTube channel on chemistry. It consists of a series of videos about chemical elements and the periodic table , with additional videos on other topics in chemistry and related fields.
Having started with only diamond and oxygen, and produced a gas which contains only carbon and oxygen, Tennant had discovered that diamonds are made of carbon. Unaware of atomic theory at the time, scientists were unable to explain how carbon, already known to exist as one of the softest substances in the form of graphite , could also be the ...
The alkali metals dissolve slowly in liquid ammonia, forming ammoniacal solutions of solvated metal cation M + and solvated electron e −, which react to form hydrogen gas and the alkali metal amide (MNH 2, where M represents an alkali metal): this was first noted by Humphry Davy in 1809 and rediscovered by W. Weyl in 1864.
Cs > K > Na > Li > alkaline earth metals, i.e., alkali metals > alkaline earth metals, the same as the reverse order of the (gas-phase) ionization energies. This is borne out by the extraction of metallic lithium by the electrolysis of a eutectic mixture of lithium chloride and potassium chloride: lithium metal is formed at the cathode, not ...
Several carbides are assumed to be salts of the acetylide anion C 2− 2 (also called percarbide, by analogy with peroxide), which has a triple bond between the two carbon atoms. Alkali metals, alkaline earth metals, and lanthanoid metals form acetylides, for example, sodium carbide Na 2 C 2, calcium carbide CaC 2, and LaC 2. [2]
The insertion of the guests increases the distance between the carbon sheets. Common guests are reducing agents such as alkali metals. Strong oxidants also intercalate into graphite. Intercalation involves electron transfer into or out of the carbon sheets. So, in some sense, graphite intercalation compounds are salts.
Sodium metal is highly reducing, with the standard reduction potential for the Na + /Na couple being −2.71 volts, [3] though potassium and lithium have even more negative potentials. [4] The thermal, fluidic, chemical, and nuclear properties of molten sodium metal have caused it to be one of the main coolants of choice for the fast breeder ...
Cyclic compounds with chalcogens, carbon group elements, and boron atoms exist, and occur from the reaction of boron dichalcogenates and carbon group metal halides. Compounds in the form of M-E, where M is silicon, germanium, or tin, and E is sulfur, selenium or tellurium have been discovered.