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Thorium reacts with hydrogen to form the thorium hydrides ThH 2 and Th 4 H 15, the latter of which is superconducting below the transition temperature of 7.5–8 K; at standard temperature and pressure, it conducts electricity like a metal. [12] Thorium is the only metallic element that readily forms a hydride higher than MH 3. [31]
Despite thorium's position in the f-block of the periodic table, it has an anomalous [Rn]6d 2 7s 2 electron configuration in the ground state, as the 5f and 6d subshells in the early actinides are very close in energy, even more so than the 4f and 5d subshells of the lanthanides: thorium's 6d subshells are lower in energy than its 5f subshells ...
Thorium resources are the estimated mineral reserves of thorium on Earth. Thorium is a future potential source of low-carbon energy. [1] Thorium has been demonstrated to perform as a nuclear fuel in several reactor designs. [2] [3] It is present with a higher abundance than uranium in the crust of the earth. Thorium resources have not been ...
For example, thallium (Z = 81) has the ground-state configuration 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 5d 10 6p 1 [4] or in condensed form, [Xe] 6s 2 4f 14 5d 10 6p 1. Other authors write the subshells outside of the noble gas core in order of increasing n , or if equal, increasing n + l , such as Tl ( Z = 81) [Xe ...
In 1953, with the help of Maurice Wilkins and Rosalind Franklin's X-ray crystallography, James Watson and Francis Crick proposed DNA is structured as a double helix. [1] In the 1960s, one main DNA mystery scientists needed to figure out was the number of bases found in each code word, or codon, during transcription.
For each atom the subshells are given first in concise form, then with all subshells written out, followed by the number of electrons per shell. For phosphorus (element 15) as an example, the concise form is [Ne] 3s 2 3p 3 .
The two base-pair complementary chains of the DNA molecule allow replication of the genetic instructions. The "specific pairing" is a key feature of the Watson and Crick model of DNA, the pairing of nucleotide subunits. [5] In DNA, the amount of guanine is equal to cytosine and the amount of adenine is equal to thymine. The A:T and C:G pairs ...
Thorium was also used in certain glass elements of Aero-Ektar lenses made by Kodak during World War II. Thus they are mildly radioactive. [15] Two of the glass elements in the f/2.5 Aero-Ektar lenses are 11% and 13% thorium by weight. The thorium-containing glasses were used because they have a high refractive index with a low dispersion ...