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Boric acid in equilibrium with its conjugate base the borate ion is widely used (in the concentration range 50–100 ppm boron equivalents) as a primary or adjunct pH buffer system in swimming pools. Boric acid is a weak acid, with p K a (the pH at which buffering is strongest because the free acid and borate ion are in equal concentrations) of ...
Borax is also easily converted to boric acid and other borates, which have many applications. Its reaction with hydrochloric acid to form boric acid is: Na 2 B 4 O 7 ·10H 2 O + 2 HCl → 4 H 3 BO 3 + 2 NaCl + 5 H 2 O. Borax is sufficiently stable to find use as a primary standard for acid-base titrimetry. [17]: p.316
Borate concentration (giving buffering capacity) can vary from 10 mM to 100 mM. As BBS is used to emulate physiological conditions (as in animal or human body), the pH value is slightly alkaline, ranging from 8.0 to 9.0. NaCl gives the isotonic (mostly used 150 mM NaCl corresponds to physiological conditions: 0.9% NaCl) salt concentration.
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. The best known of these is the tetraborate ion [B 4 O 7] 2−, found in the mineral borax: 4 [B(OH) 4] − + 2 H + ⇌ [B 4 O 5 (OH) 4] 2− + 7 H 2 O
Other formulations have been developed over time. In 1916, Marcel Daufresne substituted sodium bicarbonate for Dakin's boric acid as buffering agent. [7] [17] This formulation is the basis of current commercial products. [18] The concentration chosen by Dakin (0.5%) was the maximum highest concentration found tolerable to the skin.
It consists of a mixture of 0.04 M boric acid, 0.04 M phosphoric acid and 0.04 M acetic acid that has been titrated to the desired pH with 0.2 M sodium hydroxide. Britton and Robinson also proposed a second formulation that gave an essentially linear pH response to added alkali from pH 2.5 to pH 9.2 (and buffers to pH 12).
Boric is a chemistry term that refers to substances containing boron, such as: boric acid or orthoboric acid, B(OH) 3; metaboric acid, an acid containing boron, HBO 2; tetraboric acid or pyroboric acid, an acid containing boron, H 2 B 4 O 7; boric oxide, specifically boron trioxide B 2 O 3; a boric ester, or organic borate; Boric may also refer to:
C A is the analytical concentration of the acid, C H is the analytical concentration of added hydrogen ions, β q are the cumulative association constants. K w is the constant for self-ionization of water. There are two non-linear simultaneous equations in two unknown quantities [A 3−] and [H +]. Many computer programs are available to do ...