Chemical formula: H3BO3

Chemical name: Boric Acid, Orthoboric Acid

Origin: NBT Chemical

Specification: 25 kg/bag

Physical properties: white powder, easily soluble in water

Chemical properties:

Preparation

Boric acid can be prepared by reacting borax (sodium tetraborate decahydrate) with a mineral acid, such as hydrochloric acid:

NA ₂ B ₄ O ₇ ·10H ₂ O + 2 HCL → 4 B(OH) ₃ [OR H ₃ BO ₃ ] + 2 NACL + 5 H ₂ O

Nature

Boric acid is soluble in boiling water. When heated above 170 °C, it splits into metaboric acid (HBO ₂ ):

H ₃ BO ₃ → HBO ₂ + H ₂ O

Metaboric acid is a white, cubic crystalline solid that is only slightly soluble in water. Boric acid melts at 236 °C, and when heated above 300 °C it further dehydrates to form tetraboric acid or pyroboric acid (H ₂ B ₄ O ₇ ):

4 HBO ₂ → H ₂ B ₄ O ₇ + H ₂ O

The term boric acid is also sometimes used to refer to these compounds. If further dehydrated, it produces boron trioxide .

H ₂ B ₄ O ₇ → 2 B ₂ O ₃ + H ₂ O

Boric acid does not dissociate in aqueous solvents like Brønsted acid , but is a Lewis acid that reacts with water molecules to form the tetrahydroxyborate ion, and is observed under Raman spectroscopy :

B(OH) ₃ + H ₂ O B(OH)−4 + H ⁺ ( K _A = 5.8×10 ⁻¹⁰ MOL/L; P K _A = 9.24)

The polyborate anions produced form solutions with pH 7–10 if the boron concentration is greater than 0.025 mol/L. The most common ion is tetraborate found in the mineral borax:

4 B(OH)−4 + 2 H ⁺ B ₄ O2−7 + 9 H ₂ O

Boric acid plays an important role in absorbing low frequency sound waves in seawater.