Overview

Boric acid (BORE-ik ASS-id) is a colorless, odorless, white or colorless powder or crystalline material with a slightly oily feeling that slowly decomposes with heat, changing first to metaboric acid (HBO₂), then to pyroboric acid (H₂B₄O₇), and eventually to boric oxide (B₂O₃). The compound's solubility is very much a factor of temperature. In cold water, about 5 grams (0.2 ounce) of boric acid dissolve in 100 mL (3.4 ounces) of water, while at 100°C (212°F), its solubility increases to 25 grams (0.9 ounce) in 100 mL (3.4 ounces) of water.

Key Facts

Other Names:

Orthoboric acid; hydrogen orthoborate; boracic acid

Formula:

H₃BO₃

Elements:

Hydrogen, boron, oxygen

Compound Type:

Inorganic acid

State:

Solid

Molecular Weight:

61.83 g/mol

Melting Point:

170.9°C (339.6°F)

Boiling Point:

Decomposes above its melting point

Solubility:

Somewhat soluble in water, ethyl alcohol, and glycerol

Boric acid occurs naturally in a number of locations where it has precipitated...