�������t¶��

Tribasic, trī-bā′sik, adj. having three hydrogen atoms replaceable by equivalents of a base—of some acids.

The solution of arsenious oxide in water reacts acid towards litmus and contains tribasic arsenious acid, although on evaporation of the solution the trioxide is obtained and not the free acid.

An acid has been defined as a compound of hydrogen, the whole or a part of which is replaceable by a metal when this is presented in the form of a hydroxide; being monobasic, dibasic, or tribasic, according to the number of replaceable hydrogen atoms in a molecule.

Tribasic sodium phosphate alone without the addition of the carbonate will also give good results.

Calcium phosphate is always prone to coagulate; it has been called the gelatinous phosphate of lime, and we have already seen how readily tribasic calcium phosphate takes the form of beautiful transparent colloidal membranes which are gelatinous in texture.