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The boron group is notable for trends in the electron configuration, as shown above, and in some of its elements' characteristics. Boron differs from the other group members in its hardness, refractivity and reluctance to participate in metallic bonding. An example of a trend in reactivity is boron's tendency to form reactive compounds with ...
For example, boron trifluoride (BF 3) combines eagerly with fluoride sources to give the tetrafluoroborate anion, BF 4 −. Boron trifluoride is used in the petrochemical industry as a catalyst. The halides react with water to form boric acid. [51] Other boron halides include those with B-B bonding, such as B 2 F 4 and B 4 Cl 4. [55]
In biochemistry, an ultratrace element is a chemical element that normally comprises less than one microgram per gram of a given organism (i.e. less than 0.0001% by weight), but which plays a significant role in its metabolism.
Micronutrients are nutrients such as vitamins and minerals required by organisms in varying quantities throughout life to orchestrate a range of physiological functions to maintain health. [1] [2] The following is a list of micronutrients used by various living organisms. For human-specific nutrients, see Mineral (nutrient).
Selenium, which is an essential element for animals and prokaryotes and is a beneficial element for many plants, is the least-common of all the elements essential to life. [ 3 ] [ 63 ] Selenium acts as the catalytic center of several antioxidant enzymes, such as glutathione peroxidase , [ 11 ] and plays a wide variety of other biological roles .
Thus boron is not a candidate for life. [38] Arsenic is toxic to life, and its possible candidacy has been rejected. [39] [40] In the past (1960s-1970s) other candidates for life were plausible, but with time and more research, only carbon has the complexity and stability to make large molecules and polymers essential for life. [41] [42] [43]
Each boron is sp 3 hybridized, and “the configuration of the three hydrogens surrounding borons B1 and B3 is approximately trigonal and suggests approximately tetrahedral hybridization for these borons which would predict bond angles of 120°.” [6]: 35 However, the boron arrangements can be classified as fragments of either the icosahedron ...
Boron deficiencies effecting seed yields and pollen fertility are common in laterite soils. [45] Boron is essential for the proper forming and strengthening of cell walls. Lack of boron results in short thick cells producing stunted fruiting bodies and roots. Deficiency results in the death of the terminal growing points and stunted growth.