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The boron in boric acid reduces the probability of thermal fission by absorbing some thermal neutrons. Fission chain reactions are generally driven by the probability that free neutrons will result in fission and is determined by the material and geometric properties of the reactor.
The Dakin oxidation can occur in mild acidic conditions as well, with a mechanism analogous to the base-catalyzed mechanism. In methanol , hydrogen peroxide, and catalytic sulfuric acid , the carbonyl oxygen is protonated ( 14 ), after which hydrogen peroxide adds as a nucleophile to the carbonyl carbon, forming a tetrahedral intermediate ( 15 ).
Another method is heating boric acid above ~300 °C. Boric acid will initially decompose into steam, (H 2 O (g)) and metaboric acid (HBO 2) at around 170 °C, and further heating above 300 °C will produce more steam and diboron trioxide. The reactions are: H 3 BO 3 → HBO 2 + H 2 O 2 HBO 2 → B 2 O 3 + H 2 O. Boric acid goes to anhydrous ...
Water boration (the addition of boric acid to the moderator/coolant) which is commonly employed in pressurized light water reactors also produces non-negligible amounts of tritium via the successive reactions 10 5 B (n, α) 7 3 Li and 7 3 Li (n,α n) 3 1 T or (in the presence of fast neutrons) 7 3 Li (n,2n) 6 3 Li and subsequently 6 3 Li (n,α ...
These thermal neutrons are immensely more susceptible than fast neutrons to propagate a nuclear chain reaction of uranium-235 or other fissile isotope by colliding with their atomic nucleus. Water (sometimes called "light water" in this context) is the most commonly used moderator (roughly 75% of the world's reactors).
Barium borate can be prepared by reaction of an aqueous solution of boric acid with barium hydroxide. The prepared γ-barium borate contains water of crystallization that can not be completely removed by drying at 120 °C. Dehydrated γ-barium borate can be prepared by heating to 300–400 °C.
This page provides supplementary chemical data on boric acid. Thermodynamic properties. Phase behavior Triple point? K (? °C), ? Pa Critical point? K (? °C), ?
This reaction is very fast, with characteristic time less than 10 μs. [13] Polymeric boron oxoanions are formed in aqueous solution of boric acid at pH 7–10 if the boron concentration is higher than about 0.025 mol/L.