Effect of various impurities on the metastable zone width of boric acid

The metastable zone width of boric acid in aqueous solutions was measured i n the presence of Ca+2 Mg-2, Cr+3, Fe+2 ions. For the measurements of metas table zone width, the polythermal method was used. The impurity concentrati on is: varied from 0 to 1000 ppm in each aqueous solution. It was: found th at the range of metastable zone width of boric acid in aqueous solutions is considerably affected by impurities. The width of metastable zone of aqueo us solution of boric acid is: reduced with increasing impurity concentratio n. In the presence of Ca+2 and Cr+3. the equilibrium saturation concentrati on is changing.