White powder crystal or three oblique surface scaly crystallization with luster.
Has a soapy feel, no smell.
Soluble in water, alcohol, glycerin, ethers and essential oil.
Tiny acid after the bitter taste with sweet.
Contact with the skin has a soapy.
No change in the air show.
Along with the water vapor volatile.
Heating to 100 ~ 105 ℃ when lose a molecule of water to form a metaborate, in 104 ~ 160 ℃ heating duration time into focal boric acid, higher temperature of water is formed.
1 mol/L solution pH of 5.
1 g 18 ml soluble in cold water, 4 ml 18 ml cold boiling water, ethanol, glycerin 6 ml boiling ethanol and 4 ml.
Solubility in water can increases with hydrochloric acid, citric acid and tartaric acid to join.
Relative density 1.
Melting point 184 ℃ (
The boiling point of 300 ℃.
The median lethal dose (
In rats, through the mouth)
Serious cause of death, when death is toxic, internal and minimum: adult oral 640 mg/kg, 8 of the skin.
6 g/kg, intravenous 29 mg/kg;
Baby oral 200 mg/kg.
10 mg/m3 maximum allowable concentration in the air.